ZOOLOGY — CASTLi: AND MARK, CRAMPTON. 22$ 



Through correspondence with Leonard Doncaster, Esq., of Birmingham 

 University, En-land, who has been studying spermatogenesis in the honey- 

 bee, and through interchange of drawings, we have been able to convince 

 him of the inaccuracy of his published conclusions as to the number of 

 chron:osomes, and he has now published (Anatomischer Anzeiger, Bd. 31, 

 Heft 6, Aug., 1907) a second article, in which he puts himself in agreement 

 with us on this point. 



Crampton, Henry E., Columbia University, New York, N. Y. Grant No. 

 137. Determination of the laivs of variation and inheritance of certain 

 Lcpidopiera. $500. (For previous reports see Year Book No. 2, p. xli; 

 Year Book No. 3, p. 136 ; Year Book No. 4, p. 276, and Year Book No. 5, 

 pp. 244-245.) Grant No. 431. The study and collection of gasteropod 

 mollusca of the genus Partnla. $3,000. $3.500- 



Grant No. 137. — The acquisition of data relating to the variation, correla- 

 tion, and inheritance of the characters of different developmental stages of 

 Philosamia cynthia was completed by the determination of the dates of emer- 

 gence of the living individuals reared during the summer of 1906. The 

 statistical treatment of the data is now progressing. 



Grant No. 431. — In prosecuting the research upon the variation, distribu- 

 tion, and mutation of snails of the genus Partula, a journey to the Society 

 Islands was undertaken during the spring and early summer of 1907, supple- 

 menting an exploration of the previous year. The Windward Islands — 

 Tahiti and Moorea — were entirely covered in the course of this year's explo- 

 rations ; 55 valleys of the former island and 20 of the latter furnishing 

 more than 30,000 specimens. Several thousand adolescent snails were also 

 obtained. As the various species of Partula are viviparous, and as more than 

 half of the adults contain young, whose characters are often distinctly ex- 

 pressed, it is possible to study the problem of inheritance in its relation to 

 species-differentiation under exceptionally favorable circumstances. The 

 material also makes it possible to give a statistical determination of specific 

 limits. While final conclusions must be withheld until a close study has been 

 made of all the material in hand, certain general statements may be made. 

 As reported by Mayer, the species of Partula are often very local in their dis- 

 tribution, like the Achatinellidae of the Hawaiian Islands. Evidence of muta- 

 tion has been secured in several cases in Tahiti, and in at least one instance in 

 Moorea. The fixity, parentage, and place of origin of the mutant forms can 

 be established with exactness. The process of specific change is proven to be 

 a continuous one for recent times, some sinistral species being slowly con- 

 verted into dextral ones. 



