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The carotenoid trade-off hypothesis states that diet-derived carotenoids are traded off among competing physiological demands, but this statement is rarely tested in ornamented females. In this study, reverse sexually dimorphic convict cichlids (Amantitlania nigrofasciata) were fed diets containing carotenoid supplementation at three biologically relevant levels for 12 wk. This treatment was followed by spectral, microscopic, and chemical analysis to determine how females allocated the pigments to tissues and how those decisions affected their ventral patch coloration. Yellow coloration of the integument increased with carotenoids in the diet, as did carotenoids deposited in ovaries, but diet did not change carotenoid allocation to skin. The results of this study suggest that females have the ability to modulate their expression of yellow coloration via an alternative coloration strategy. Gonadosomatic index and tank environment were also related to ventral patch color, supporting previous behavioral work highlighting the importance of social selection in reinforcing signal honesty.

We present the first detailed analysis of carotenoid pigmentation of the integument of guppies (Poecilia reticulata Peters), quantifying variation in carotenoid content and composition of wild guppies from three drainages on Trinidad (1) between the sexual and general pigmentation of males, (2) between the sexes, and (3) geographically in relation to carotenoid availability. We report that the carotenoid pigments in the integument of guppies are predominantly esters of tunaxanthin. The peak wavelength of carotenoids in the orange spots of males lay only ca. 2.8 nm higher than that of pigments outside of the orange spots, and the peak wavelength of carotenoids in the male whole integument does not differ from that in the female whole integument. Carotenoid composition of the general integument of females and the non-orange spot fraction of males, but not of the orange spot fraction of males, varied with diet, correlating with the ratio beta-carotene to lutein in the different streams. Male guppies deposit higher concentrations of carotenoids in their orange spots than in the rest of the integument (five to nine times higher), but not at the expense of the general integument, which was similarly endowed as the general integument of females, even in carotenoid-poor streams. Presumably males absorb/retain more pigments than females. Photoreceptor-based simulations suggest that tunaxanthin provides both greater brightness and chroma than would 4-keto-carotenoids such as astaxanthin.

Leeches Hirudo medicinalis were exposed to either artificial pond water (APW; 1 mM NaCl) or to high-salinity conditions (HS; 200 mM NaCl) for several days. The aim of the study was to assess whether transepithelial ion conductances in their dorsal integuments were affected by this long-term acclimation. In voltage-clamp experiments using Ussing-type chambers, the transepithelial potential V(T) was clamped to 0 mV, and amiloride-sensitive currents (I(ami)) and total Na(+) transport (I(Na)) were determined. Apical Ca(2+)-free conditions strongly increased I(ami) to a similar magnitude in both differently acclimated integuments. Apical application of the lanthanide gadolinium0.1 mM decreased the short-circuit current (I(sc)). In contrast, higher concentrations up to 10 mM Gd(3+) upregulated I(sc) by an additional 90% in APW integuments and by an additional 300% in HS integuments. This Gd(3+) effect was due to a doubling of I(Na) in APW and a more than sixfold increase of I(Na) in HS integuments. In summary, the macroscopic electrophysiological variables, including I(Na), were generally not affected by long-term exposure to high salinity. However, the presence of Gd(3+)-sensitive Na(+) conductances or regulating structures were greatly upregulated during HS acclimation.

Similar to those of the gills of adults, three types of mitochondria-rich (MR) cells with different morphologies of apical surfaces (wavy convex, shallow basin, and deep hole) were identified on the integument of freshwater-acclimated tilapia larvae (Oreochromis mossambicus). The object of this study is to test the hypothesis that these subtype cells may represent MR cells equipped with variable efficiencies in Cl(-) uptake. Larvae acclimated to low-Cl(-) =0.001-0.007 mM) water developed higher densities of MR cells than those acclimated to high-Cl(-) =7.3-7.9 mM) water. The percentage of wavy-convex-type cells in total MR cells was higher in low-Cl(-)-acclimated larvae than in high-Cl(-)-acclimated larvae, which displayed only deep-hole type. In addition, Cl(-) influx rates of whole larva measured with (36)Cl(-) showed a coincident correlation with MR cell densities, that is, low-Cl(-) larvae displayed higher Cl(-) influx rates than did high-Cl(-) larva, suggesting that tilapia larvae develop a higher density of MR cells with larger apical surfaces (wavy-convex type) to boost Cl(-) uptake in Cl(-)-deficient water. The distinct types of apical surfaces may represent different phases of MR cells that possess different efficiencies of Cl(-) uptake. Increased apical membrane surface areas of MR cells may provide larvae with rapid regulation of Cl(-) before new MR cells differentiate.

More than 150 permineralized ovules of Carpolithus konopeonus Langford, preserved in sideritic concretions, have been recovered from the Middle Pennsylvanian (Westphalian D) Mazon Creek flora of northeastern Illinois. Ovules were borne apically on slender branching structures. The sarcotesta is bilaterally symmetrical with a pair of distinct lateral wings and, at the apex of the ovule, forms a prominent funnel that leads to the micropyle. The sclerotesta is radially symmetrical with a prominent beak and collar at the apex. The nucellus is free from the integument except at the base and extends into the basal part of the micropylar tube. The apex of the nucellus forms a distinct pollen chamber. Ovule vasculature consists of six or more bundles in the sarcotesta and a continuous sheath of vascular tissue in the nucellus. Pollen preserved in the micropyle and pollen chamber is of the Monoletes-type The Mazon Creek material is assigned to a new species of Stephanospermum Brongniart as S. konopeonus (Langford)...

Rates of cutaneous evaporative water loss (EWL) were measured in Anolis carolinensis lizards following their exposure to humid (80%-85% RH) or dry (35%-42% RH) environments. After 8 d of acclimation, lizards exposed to dry air had significantly reduced rates of EWL, whereas those exposed to humid air did not. Acclimation of EWL occurred regardless of whether lizards exposed to dry conditions were allowed to dehydrate (to 80% of initial mass) and regardless of whether lizards molted. Evaporation rates measured from isolated dorsal skin in vitro demonstrated that dry-acclimated lizards had a lower skin permeability than did humid-acclimated lizards. The differences in permeability disappeared when lipids were extracted from the skin. Our findings suggest that acclimation of integumentary permeability may result from the gradual deposition of lipids in response to a local stimulus acting at the integument.

nective tissue of the dermis with the underlying dermal bones. In casqueheaded frogs of the family Hylidae, integument which overlies the coossified dermis shows a reduction in number of glands and is poorly vascularized (Trueb 1970). The functional significance of coossification is not clear. We here report experimental evidence which demonstrates that coossification in extant frogs is associated with reduction of evaporative water loss from the integument of the head.

The internal changes which occur during the periodic removal and redevelopment of the chitinous portion of the integument of insects are little understood and but few observations have been made thereon. In this paper are given observations and conclusions concerning some of the changes found in the integument of Leptinotarsa decimlineata and Chrysobothris femorata. These two beetle larvae are good examples of two types of larvae, the first living freely exposed upon their food plants and are typical examples of those insect larvae which pass their lives upon plants in exposed places and must go through ecdysis exposed, and the second of larvae that live in burrows or cells, protected from external interference to a great degree. Corresponding to the difference in their habitats they show differences in the internal changes accompanying ecdysis. The life of an insect larva is made up of a series of instars or stages, each of which represents a very precise cycle of development and physiological activities. These cycles of changes are of interest and serve to give a good basis for the orientation of the changes which I am about to describe as accompanying ecdysis. The changes within a single cycle are given in the tabulated form on page I77. Each larval stage properly begins with the period of growth following the reconstruction period of the preceding ecdysis and ends with the end of the next reconstruction period. Looked at from the exterior the stages extend from ecdysis to ecdysis, but as shown in the above table the period of exuviation is the middle one of the short and rapidly passed over periods in which the process of ecdysis is begun, achieved and the animal recovers from the effects thereof. The changes with which this paper deals are confined largely to the last three periods in the cycle. 176

1. In the Phormia regina larva oxygen uptake from air at 25° of larvae with both pairs of spiracles ligated off is about 0.09 µL/mg. live wt./hr. (10% of normal respiration) and increases four-fold in oxygen. This is the maximum cutaneous uptake possible from air.2. The posterior pair of spiracles by itself can admit enough oxygen from air to supply normal needs.3. On the basis of reciprocal ligation experiments, the anterior spiracles have about half the "capacity" of the posterior spiracles for admitting oxygen into the tracheal system, and can, by themselves, admit about 60% of normal needs.4. The internal pO2 in larvae with both pairs of spiracles ligated is zero, even in an atmosphere of pure oxygen.5. In normal (non-hypoxic) larvae, cutaneous respiration accounts for less than 2.5% of the total oxygen uptake.6. The permeability of the integument to oxygen is of the order of 0.005 µL/mm.2/min./atm.7. DDT does not affect cutaneous permeability to oxygen.8. DDT-poisoned larvae cannot obtain enough oxyg...

1. The characteristics, distribution and habitat of the millipede, Luminodesmus sequoiae Loomis and Davenport are discussed. The life-history and the development of the male gonopods are described.2. Luminescence is continuous, under no voluntary control, and first appears on hatching; its source apparently lies in the deeper layers of the integument.3. Extracts of Luminodesmus glow briefly and go out. Experiments to elicit a light flash from such extracts with combinations of Photinus lanterns, magnesium ion and adenosine triphosphate, and to demonstrate classical "luciferin-luciferase" activity have been without success. The integument of Luminodesmus gives a brilliant yellow-green fluorescence in ultra-violet light.4. Nitrogen atmospheres reversibly extinguish luminescence, carbon dioxide irreversibly so, while cyanide has little effect on luminescence until the lethal point is reached. Chemical and biological tests have indicated that Luminodesmus, like other millipedes, releases HCN.

1. The identification of a proprioceptive organ (PDO), spanning the propodite-dactylopodite joint in the crab, Sesarma reticulatum, has extended the study of the PDO to the family Grapsidae.2. The appearance and physiological response of the (PDO), in Sesarma are essentially identical to the appearance and response found by Wiersma and Boettiger (1959) inthe Carcinus PDO.3. A dactylopodite-moving stimulator is described; it provides a variable and controlled stimulus to the organ, allowing quantitative comparisons of the PDO output in proecdysis, postexuvial, and in intermolt stage crabs.4. Sensory input from the PDO does not vary in proecdysis animals from Drach stage mid D to exuviation, and in the immediate postexuvial stages, as compared to the response from intermolt crabs.5. The constancy of the PDO output is discussed in terms of the organ's attachment to the integument.

1. The stony layer in seeds of gymnosperms is integumental in origin as far as the integument extends, and in the angiosperms studied it is carpellary. In cycads both the outer and inner fleshy layers contribute to the formation of the stony layer. In Ginkgo, Pinus, Juniperus, and Torreya the stony layer originates from the outer fleshy layer. In Gnetum it originates from the inner region of the outer integument. In Sassafras the stony layer originates from the interior epidermal cells of the carpel. In Quercus velutina it is the exterior subepidermal layer that differentiates into the stony layer. In Prunus the interior subepidermal layer of the carpel divides and forms the stony endocarp. 2. There are simple and complex stony layers. In cycads the stony layer is made up of isodiametric cells and elongated longitudinal cells. In Ginkgo the situation is the same. In the Coniferales there is the start of the complex stony layer. There are isodiametric cells, elongated transverse cells, elongated longitudin...

1. From the results of measurements of O2 uptake and CO2 output in the sealed silkworm, it was confirmed that the gases penetrate through the integument both in the larva and pupa. The rate of O2 uptake as well as CO2 output is reduced to about one-fiftieth of the controls in the sealed silkworm. The R. Q. value of such silkworms ranged from 1.00 to 1.20 in the larva and was about 1.50 in the pupa. The rate of respiration became lower with the time lapse after occlusion, the decrease being more remarkable in the larva than in the pupa. Throughout the larval and pupal stages, the rate of O2 uptake decreased less than that of CO2 output.2. The permeability of the skin rubbed just before occlusion increased a few times, the ratio being a little higher in the larva than in the pupa. The rate of increase in CO2 output was about one and one-half times that in O2 uptake both in the larva and pupa. The decrease of the volume of measured gases seen with the time lapse in the rubbed material was not so remarkable i...

1. The mice reacted to evaporation whether it was produced by movement, dryness or heat (p. 192, 194-195).2. The negative reactions to air of high temperature which gives the same amount of evaporation as dry air is no sharper than in the case of dry air with no difference in temperature (p. 192, 196).3. They behaved normally in air of low evaporation, their optimum, but when the evaporation was increased the mouse was stimulated and reacted negatively (p. 192, 194).4. Slight differences in air movement were easily detected by the mice (p. 195).5. The rate of evaporation is the best index of the combined action of wind, temperature, and dryness of the air.6. The integument of animals is important in determining the rate of evaporation, and animals in the same community show differences in their ability to withstand unfavorable conditions. The hair of the mouse makes it nearly as resistant as the heavily chitinized insects.7. Evaporation is probably the most important factor in determining the distribution...

It is always welcome to see attention being paid to what are usually regarded as old-fashioned" phylogenetic speculations. The application of new ideas to old themes is seen in the recent article by Cauna (1963) suggesting a new theory for the origin of paired vertebrate appendages. Cauna's thesis is that appendages first arose as elongate sensory tentacles; and, although he does not concern himself with their subsequent evolution, it may be assumed that he regards their locomotor functions as secondary. Cauna's evidence may be conveniently divided into three categories. The first is concerned with the hairless nature of the mammalian palm and sole and their equivalent in non-mammalian vertebrates, whose sensory functions the author regards as primitive. Secondly, Cauna states that these regions of the integument arise during embryogenesis from the ectoderm of the apical ridge. Thirdly, he believes that the palmar/plantar integument thus derives from ectoderm which is part of the specialized "lateral placode system." The present author's studies on the structure and development of the skin of reptiles (Maderson, 1965a,b) and unpublished data on the integument of other non-mammalian vertebrates shed further light on this interesting theory. A problem which arises when one attempts to consider the first part of Cauna's thesis is one of definition. He does not state clearly what is meant by the "equivalent (of the "palm/sole" integument) in nonmammalian vertebrates," except that there is a direct implication that the nonfeathered portion of a bird's leg represents this. If one believes that the scaled region of a bird's leg represents a retention of the ancestral reptilian integument, one is forced to assume that Cauna would homologize the integument over the portions of the reptilian limb distal to the radius-ulna and tibiofibula to the palmar/plantar integument of mammals. Such a relationship would appear highly unlikely, and the present author's unpublished observations on the scaled limb integument of chicks and lizards provide no evidence to support such a suggestion. Furthermore, Cauna does not mention any publications which demonstrate a specialized sensory function of the limb integument in nonmammalian vertebrates comparable to that known in some mammals (see references, Winkelman, 1965). In fact, there are epidermal structures which are called "sense organs" (Schmidt, 1920; Preiss

1. An anatomical study has been made of additional, small petrified seeds from two Illinois coal-ball localities. 2. Taxospermum undulatum sp. nov., an ovoid seed with only slight lateral flattening, is included in the Cardiocarpales. 3. Coronostoma quadrivasatum gen. et sp. nov. has structural characteristics which relate it to the seed genera Conostoma and Lagenostoma in the Lagenostomales. 4. Conostoma quadratum Graham, which was originally described only from transverse sections, is more completely described from longitudinal sections which include the region of the lagenostomc and the apical and basal modifications of the integument.

1. A study was made of the endospermembryo relationship in the developing seed of Taraxacum officinale, a fully fertile, autonomous apomict. A related sexual species, T. kok-saghyz, served as the control. 2. Seed development in T. kok-saghyz follows the pattern characteristic of the angiosperms. Endosperm and embryo development are initiated by double fertilization, and the two tissues are closely correlated in their subsequent growth. The endosperm is less precocious, however, than in most flowering plants. The mature ovule is low in food reserves. 3. The T. officinale ovule stores a large mass of protein-rich nutrient material in the integument. Endosperm and embryo begin development without fertilization and apparently quite independently of each other. During the ensuing growth there is extreme diversity in the size ratios of the two tissues from seed to seed in the same head. For example, the embryo may attain a relatively advanced, and normal, development, while the endosperm remains one-celled. Con...