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Results are presented for 16 National Forage Variety Trials of annual and short-term hybrid ryegrass cultivars conducted in Waikato, Taranaki, Manawatu, Canterbury and Southland. In all, 30 cultivars (17 named, 13 experimental) were included. Cultivar effects were significant in all seasons, and for the annual totals. Cultivar differences were greatest in summer. Spring production accounted for over 40% of annual totals and summer production less than 20%, but it was summer production that was more closely correlated with the individual cultivar annual total. Over all trials and cultivars, regrowth in the second autumn accounted for 11% of the total for 12 months beginning in the winter following sowing. Comparing North Island sites with Canterbury sites, there was some indication of cultivar × region interaction, particularly in summer. Patterns of interaction of cultivars with trials were examined, and indicated that some cultivars can be grouped as having similar responses. Repeated trials at the same site were sometimes but not always consistent in ranking cultivars. The results indicate that some cultivars do perform consistently better than others, for particular seasons or for annual totals, so that the trials are a reliable indicator of which new experimental cultivars should be released to the market. The results also indicate that several trials are necessary to determine the merit of a wellperforming cultivar. The error associated with the mean of cultivars present in only one or two trials is high (standard deviation approaching 20% of the mean in some seasons). This may, however, be sufficient to eliminate poorer experimental lines from further consideration. Keywords: Italian ryegrass, hybrid ryegrass, cultivars, Lolium × boucheanum, Lolium multiflorum, pasture agronomy

The Scottish Marine Biological Association has a historical link with the Royal Society through the Challenger Expedition which took place in response to representations by the Council of the Society. Its inspirer and director was Professor Charles Wyville Thomson of Edinburgh, and the administrative centre for the working out of its results was situated in that city. After Wyville Thomson’s premature death in 1882 his place was taken by the senior naturalist of the expedition John Murray. In addition to his work as Head of the Challenger Office, Murray, with the financial aid of many personal friends, founded the small Scottish Marine Station built at the margin of a submerged quarry at Granton and having as tender a small yacht the Medusa , fully equipped with sounding and dredging apparatus, and a floating barge laboratory the Ark . The activities of the station under its superintendent J. T. Cunnings ham were directed specially towards fishery problems—the spawning grounds of the herring, the pelagic eggs and larvae of the other food fishes, and that special enemy of the line fishermen, the hagfish Myxine .

1. The fore-gut first becomes folded off from the main mass of yolk-cells. 2. The pyloric valve arises by the hind end of the fore-gut being pushed back into the cavity oE the mid-gut. 3. The main mass of yolk-cells becomes gradually "modelled" into a spirally-coiled intestinal rudiment. 4. The main part of the buccal lining is developed in situ from large yolk-cells. 5. The part of the ventral side of the head, on which, are the olfactory rudiments, becomes enclosed in the buccal cavity by the development of the upper lips and by the forward growth of the lower jaw. 6. The olfactory opening becomes divided into anterior and posterior tiares by the apposition and fusion of the intermediate portion of its lips. 7. The thyroid arises as a solid downgrowth from the buccopharyngeal floor, which gradually becomes cut off from behind forwards. 8. The tongue is a primary tongue like that of Urodeles, but without gland-field. 9. The lung arises from a solid mid-ventral rudiment. 10. When the lung becomes bilobed, the (actual) right lobe is for a time small in size as compared with its fellow. 11. Complicated torsional processes take place during the development of the lung. 12. Through the dorsal mesentery becoming partially merged in the splanchnocoele roof, the lungs come to lie outside the splanchnocoele.

RECENT attendance at the discussions of the Institut International d'Embryologie and of the British Association (Section D) has impressed on me the desirability of offering—more especially to the younger generation of researchers in zoological science—a short statement of personal experience emphasizing certain general considerations, which are in my opinion useful as affording guidance along profitable lines of investigation and at the same time warning against dangerous pitfalls. I have been, in my time, responsible for a considerable number of new facts and theories relating, on one hand, to the evolutionary history of vertebrates and on the other to the general theory of evolution. I will not burden this note with bibliographical details, but refer anyone interested to my text-books on “Vertebrate Embryology” (Macmillan, 1919) and “Evolution” (Macmillan, 1926).

SynopsisThe subjoined Note summarises an investigation into the skeleton of the pectoral fin of a common Selachian—Acanthias vulgaris—with the object of determining whether, and if so, to what extent it shows any vestige of the archipterygial type of structure. To this end careful examination was made of five hundred random embryos, and the result demonstrated the general occurrence of vestigial post-axial rays at the tip of the fin. The suggestion that such rays—stated by Braus to occur in a specimen of the embryo of Centrophorus—are to be regarded as a mere casual variation without evolutionary significance is thus shown to be devoid of weight, and the pectoral fin skeleton of Selachians established definitely in line with that of Pleuracanthus and Ceratodus.

My main purpose in the following short paper is to publish figures illustrating some of the more important facts of the early development of myotomes and motor nerves in Lepidosiren. The bearing of some of the observations of nerve development upon current theories renders it particularly desirable that they should be illustrated by untouched photographs of the sections. A few photographs illustrating the more important stages in the development of the motor nerve trunks are given on Plate I. For the preparation of the photographs here published, as well as several others, I am indebted to the skill of my friend Dr T. H. Bryce, and of Mr Fingland, our University photographer.

The following paper constitutes the first instalment of an account of the development of Lepidosiren . The material upon which it is based was obtained during a sojourn which I made for the purpose amongst the swamps of the Gran Chacot during the years 1896 and 1897. I should in some ways have preferred not to publish until in a position to give a fairly complete and rounded off account of the whole of the phenomena of development. This would, however, have meant very considerable delay, and I am induced to publish the set of drawings illustrative of the external features, both by the advice of my friends and by the fact that this will serve to make known those features in the development which are after all of the greatest general interest. It will be time enough when the research is completed to point out any conclusions that may be drawn from it as to the affinities of the group to which Lepidosiren belongs; but I may be allowed even now to draw attention to one point which seems to me to lend unusual importance to the features attending its development. That is the peculiar conditions under which the development will be found to take place—in a secluded retreat, in which, while able to hatch at a comparatively early stage, the larva continues to exist, performing only those vital processes necessary to all life, sheltered effectually from having to fight for itself amongst those ever recurring changes in environment, which bring in their train the hiding away under a veneer of adaptation of features due to long heredity and of phylogenetic importance. The development of Lepidosiren under such conditions of seclusion—conditions, too, which probably remain constant over very long periods of time—is enough, I think, to lend a very special interest to its developmental phenomena, quite apart from the interest they must have as belonging to one of the Dipnoi and to the first of the Dipneumona which has fallen under embryological investigation.

Arthur Willey was born at Scarborough on 9 October 1867, second son of the Reverend William Willey, a Wesleyan minister. From Kingswood School, Bath, at that time reserved for the sons of Wesleyan ministers, he passed to University College, London, where his boyish interest in Natural History was stimulated and disciplined under the inspiring influence of that great teacher Edwin Ray Lankester, and this was no doubt the determining influence in his choice of a professional career. Willey entered University College in 1887 taking as his subjects for the degree of B.Sc., zoology, geology and botany. He graduated in 1890 with first-class honours in zoology.

Johannsen’s work on inheritance within “populations” of beans, extended as it has been by subsequent workers, forms a fitting complement to the Mendelian hypothesis, and the two conceptions together have enabled our knowledge of genetics to increase by leaps and bounds. The object of the present work, which was begun some years ago and which has extended beyond the limits at first planned, was to investigate inheritance within parthenogenetic animal populations from the point of view of Johannsen’s well-known work. The terminology adopted is accordingly in agreement with that introduced by him, in spite of the fact that some objections have been raised to the use of the word genotype in Johannsen’s sense, on the grounds of its prior usage with a different meaning by systematists. Where it is necessary to express the group of individuals descended asexually (in our case parthenogenetically) from a, single ancestor, the word clone has been used, following Shull. As this author points out, the extension of Johannsen’s term pure line to include groups of individuals related in this way is not legitimate. It must be distinctly understood that a genotype, and hence the individuals forming a biotype, need not be homozygous as long as they all have the same factorial composition. In sexual reproduction such heterozygous biotypes are easily recognised on breeding, but in asexual reproduction where Mendelian segregation is not taking place, they cannot be distinguished in this way from homozygous ones.

Summary The more important features in the morphology of the male urogenital system of Lepitlosiren and Protopterus may be summarized as follows:— 1 The testis is very much elongated and is divisible into an anterior formative and n posterior vesicular and conducting region. 2 The posterior part of the vesicular region is connected with the tubules of the hind end of the mesonephros, which serve for the passage of the genital products. 3 In Protopterus the testis is connected with the kidney only at its extreme tip; in Lepidosiren there is a stories of about half a dozen segmentally arranged vasa efferentia which open into Malpighinn capsules. 4 In Protopterus the hind genital region of the kidneys is clearly marked off from the rest, and in this region the kidneys are fused across the middle line; in Lepidosiren there is only a slight attempt at this differentiation, and the kidneys of the two sides are posteriorly, as elsewhere, quite distinct. 5 The Wolffian ducts open in the adult inale by a common (Protopterus) or by two separate (Lepidosiren) papillae into the distal portion of the cloacal caecum, which is morphologically a urogenital sinus formed in ontogeny as a dilatntion of the fused, but originally separate, posterior portions of the Wolffian ducts.

THERE has just reached me the Proceedings of the Linnean Society for October, containing the report of an interesting discussion upon the “Origin of Vertebrates” which took place at meetings of the society in January and February of this year. Apart altogether from statements as to matters of fact which seem to be open to challenge, this discussion appears to me to raise points in regard to the methods employed by the morphologist which are of practical importance to those interested in the science of morphology.