Phylogenetic relationships among 7 members of the Anopheles hyrcanus species group of East Asia which contains vectors of human parasitic diseases were studied based on the development of interspecific hybrids; they were compared with phylogenetic relationships obtained from morphological and biochemical works. A study of Takai et al. (1984) on postmating reproductive isolation between 7 members of the An. Hyrcanus species group demonstrated various degrees of development among hybrids. It is proposed in this study that hybrid development is correlated with phylogenetic relationship. An index of hybrid development was introduced and was applied to classification of the parental members. It was compared with a classification based on the morphological data of Harrison (1972) which were reanalyzed in this study. The data for polypeptide differences disclosed by two-dimensional gel electrophoresis conducted by Imajoh (1981) were reanalyzed to construct a classification, which was compared with the present results. A common clustering among the three classifications was a grouping of An. Argyropus, An. nigerrimus, and An. Nitidus. Laboratory colonies of this subgroup were difficult in free-mating in cages and preferred to feed on man, whereas colonies of the other species freely mated in cages and preferred to blood-feed on mice, except that An. crawfordi did not freely mate in cages. Relation of the vector members to the classification is discussed. A revision in the UPGMA method is also presented.

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Median effective dose (ED₅₀) of diethyl ether was determined using loss of "avoidance reflex". The ED₅₀ in an ether-resistant mutant strain, Eth-29, was 2.90%atm in females and 3.02%atm in males and that in an ether-sensitive strain, bw; st; svⁿ, was 1.69%atm in females and 1.71%atm in males. The sensitivity to gamma-irradiation of ⁶⁰Co was evaluated by knock-down: the ED₅₀ in Eth-29 was 1.20kGy in females and 1.16kGy in males, while the ED₅₀ of bw; st; svⁿ was 1.59kGy in females and 1.50kGy in males. The Eth-29 was more resistant to ether anesthesia and more sensitive to gamma-irradiation than bw; st; svⁿ. The ether resistance and radiation sensitivity in the F1 progeny of reciprocal crosses between Eth-29 and bw; st; svⁿ, were intermediate between those of their parents. From chromosomal analysis, using synthesizing strains by chromosomal substitution between Eth-29 and bw; st; svⁿ, it was revealed that the major gene(s) of the ether resistance and radiosensitivity were located on the second chromosome and minor gene (s) on the third chromosome. The opposite effects between ether anesthesia and ⁶⁰Co γ-radiation damage in Eth-29 were proved at chromosomal level. Both knock-down and loss of avoidance reflex refer to a state of dyskinesia associated with convulsion and paralysis, and which involves disfunction of the central nervous system, We propose that ether resistance and radiosensitivity in Eth-29 of the central nervous system have developed simultaneously.

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Genetic variation of regulatory genes with respect to the amylase activities in different developmental stages (developmental inducibility) as well as the inducibility (S/N) which was studied in the previous reports (Yamazaki and Matsuo 1984), was found among 10 isogenic strains established from a natural population of Drosophila melanogaster. Net fitness of each of these 10 strains was obtained from interspecific competition experiments and the correlation between fitness and inducibilities of amylase was calculated; No correlation was obtained between developmental inducibility and fitness. On the other hand, a significant positive correlation was obtained between fitness and inducibility (S/N) (γ_p=0.48^* and γ_g=0.95). This indicates that these two types of regulatory gene polymorphisms are different in nature, and that regulatory patterns of the enzymes which are found in different developmental stages under normal environments have little to do with adaptability of flies.

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The frequency of deleterious second chromosomes carrying recessive lethal or semilethal genes has been surveyed for the past 15 years in the Anyang, Korea, population of Drosophila melanogaster. It remarkably increased from about 32% (1973) to 45% (1978) and then decreased to about 30% (1983). The rise and fall of the deleterious chromosomes consisted of two similar but phase-shifting changes in lethal and semilethal frequencies. The latter occurred two or three years after the former change. The allelism rate among lethal chromosomes increased during the period, especially from 1971(0.55%) to 1980 (3.68%). Comparison with other data from the same population suggested that some mutator factors, such as the P element, may have invaded the Anyang population in the sixties.

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We analyzed mitochondrial DNA purified from the livers of 10 Japanese monkeys, Macaca fuscata, derived from four local populations using the cleavage patterns for 18 restriction enzymes. Of the 18 enzymes used, polymorphism of the cleavage patterns was observed in 12 enzyme digestions. By combining the cleavage patterns for each enzyme, the 10 samples were classified into four restriction types. Each of the four types was found exclusively in the respective population from which the samples were obtained. Each type had 43 to 49 sites for the 18 enzymes. The average number of nucleotide substitution per site was estimated to be 0.0132. This value is several times larger than that observed in human population but at approximately the same level compared with those observed in great apes and rodents. The phylogenetic tree constructed for the four types indicate that mtDNAs of the 10 Japanese monkeys examined were divided into two clusters and these two clusters diverged approximately one million years ago. This work has proved that the restriction enzyme analysis is useful for elucidating genetic variations in Japanese monkeys.

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Twenty-one F₁ hybrids among fourteen varieties or cultivars of cultivated form of Emmer wheat were studied with respect to chromosome pairing at MI of PMC′s, and four chromosome types were determined according to the reciprocal translocations detected. In relation to LD 222 type that was recognized as a standard, Ethiopicum type had a reciprocal translocation between 2A and 4A, and two translocations among three chromosomes, i.e. 4A-2A:2A-2B, were carried by Abyssinicum type. Liguliforme type had two different translocations, the one being between 7A and 5B, but the other unidentified.

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