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Allen explores Arithmetic books used in American schools before 1850 which stated the arithmetic problems in the form of verse. For several generations of American schoolboys, the verse problem is seen to have been a part, admittedly a small part, of arithmetic and related studies. The verse problem varied, in its depth and complexity, from merely the casual and interesting, to the difficult, challenging, and decidedly unusual.

Discussed Canada's entrance into the use of the metric system and how that system will affect the world. (RK)

1. 1. The hemolymph sugars of honey bees ( Apis mellifera ) were determined by spectrophotometric and gas-liquid chromatographic methods. 2. 2. A new phenol-acetate reagent was developed that enabled quantification of trehalose in the presence of sucrose. 3. 3. The results of these analyses provide insight into the means by which honey bees utilize hemolymph sugars for energy for flight.

The probing behavior of four biotypes of the spotted alfalfa aphid, Therioaphis maculata (Buckton), feeding on resistant and susceptible alfalfa clones (genotypes) was investigated. Salivation, X-pattern, and ingestion waveforms, and probing sequences were similar among four biotypes probing the substrate of a susceptible clone. On one resistant clone (‘Moapa’ C-905) probing sequences produced by biotypes A and C were similar but abnormal; stylet penetration of the phloem sieve element and ingestion were lacking or greatly suppressed. On another resistant clone (Moapa C-908) probing sequences produced by biotype A were normal whereas those produced by biotype C were abnormal; stylet penetration of phloem sieve elements and ingestion were completely lacking. The salivation probe was successfully completed by both biotypes on the resistant clones; salivation time was significantly longer on the resistant clone than on the susceptible clone. The data suggest that the mechanism of resistance is based on a chemical interaction between the plant and aphid, and that the system is related to the phytoalexin theory of host-plant resistance and to the phenol-phenolase reactions of plants and sap-sucking insects. Zusammenfassung PROBEVERHALTEN VON BIOTYPEN DER LUZERNEZIERLAUS AN RESISTENTEN UND ANFALLIGEN LUZERNEKLONEN Untersucht wurde das Probeverhalten von vier Biotypen der Luzernezierlaus (Therioaphis maculata (Buckton)) an resistenten und anfalligen Luzerneklonen (Genotypen) mit Hilfe der McLean-schen elektronischen Messung. Dabei wurden die drei Wellenformen (1) fur Speichelfluss, (2) fur das Eindringen in ein Siebelement (= X-pattern) und (3) fur die Nahrungsaufnahme graphoanalytisch aufgenommen und analysiert. Auf anfalligen Klonen war das Probeverhalten, gemessen an Form und Abfolge von (1)–(3) bei allen Biotypen gleichartig. Dagegen waren auf einem resistenten Klon („Moapa” C-905) die Probestiche der A- und C-Biotypen zwar ahnlich aber anormal: Stechborstenpenetration in das Siebelement und Nahrungsaufnahme daraus waren stark gehemmt bzw. fehlten. Bei einem anderen resistenten Klon („Moapa” C-908) waren die Probestiche des A-Biotypus normal, wahrend die des C-Biotypus anormal waren; beim letzteren unterblieben Stechborstenpenetration in das Siebelement und Nahrungsaufnahme vollstandig. Bei beiden Biotypen lief die Speichelflussphase auf resistenten Klonen erfolgreich ab; die Dauer des Speichelflusses war dabei auf resistenten Klonen bedeutend langer als auf anfalligen. Die Daten weisen darauf hin, dass der Resistenzmechanismus auf einer chemischen Interaktion zwischen Wirtspflanze und Blattlaus beruht und dass dieser Mechanismus in Zusammenhang gebracht werden kann mit der Phytoalexintheorie uber die Resistenz der Wirtspflanze und mit den Phenol-Phenolasereaktionen zwischen Pflanzen und saftsaugenden Insekten.

Six biotypes of Therioaphis maculata (Buckton) have now been recognized in western United States. Among these, four are recent discoveries and were identified from results of a combination of studies including tests on the parent clones of ‘Moapa’ and ‘Washoe’ alfalfa, Medicago saliva L., biological activity, and response to sonic organophosphate insecticides. The new biotypes have been designated ENT-C, ENT-D, ENT-E, and ENT-F.

Ancient numerals, like dead languages, have lessons to teach, and a unit on the number systems of other times and places may provide the kind of enrichment which enhances understanding and appreciation of the simple, effective decimal system we employ. Roman numerals are introduced to all pupils, normally in the modified form in which they appear on clock faces, chapter headings, and engraved dates.

Fifty-two experimental alfalfas and cultivars were evaluated for resistance to 4 biotypes (ENT-A, ENT-C, ENT-E, ENT-F) of Therioaphis maculate (Buckton) in greenhouse tests at Tucson, Arizona. Three alfalfas (‘Caliverde’ 65, developed by the University of California at Davis; T-3-12, a new experimental developed jointly by the University of Arizona and Entomology Research Division, ARS, USDA; and UC-64, a new experimental developed jointly by University of California and Entomology Research Division, ARS, USDA) were rated highly resistant, 14 moderately resistant, 13 intermediate, 7 low resistant, 9 susceptible, and 6 highly susceptible. In the analyses, highly significant differences were found in seedling survival. Also, differences among biotypes were highly significant, and the biotypes reacted differentially among and within alfalfas, thus substantiating previous experiments that they are distinct. When the virulence of biotypes was established, ENT-F was found to be the most virulent strain, followed by ENT-E, ENT-A, and ENT-C.

A new virulent biotype of Therioaphis maculata (Buckton) was collected from populations infesting ‘Mesa-Sirsa’ alfalfa at Mesa and Poston, AZ. The new strain, designated H, and biotype F, reproduced and survived on 6 of 9 parent clones of ‘Moapa’ alfalfa. Clone C-907 was susceptible to H and resistant to F, clearly separating the 2 closely related biotypes. Both biotypes were identically susceptible to 4 organophosphate insecticides.

The interaction between virulence in Therioaphis maculata (Buckton) and resistance in ‘Hayden’ and ‘Lahontan’ alfalfas was investigated. Evidence of a gene for gene relationship was found between biotypes (C, A, E, F, H) of the spotted alfalfa aphid expressing genes for virulence and in plants selected from Hayden expressing corresponding genes for resistance. This relationship was not evident between these same biotypes and plants selected from Lahontan alfalfa. The relationship in Hayden appears to be oligogenic (specific) since resistance to avirulent biotypes was not conferred in plants to virulent biotypes. The genic system in Lahontan was unusual and may be polygenic or oligogenic (general) since all plants selected for resistance to avirulent biotypes were equally resistant to virulent biotypes and vice versa. Lahontan alfalfa should be fully exploited so that these traits can be incorporated into alfalfa cultivars where polygenic resistance to the spotted alfalfa aphid is desired.