NOTES AND LITERATURE 



BIOMETRICS 



Recent Quantitative Studies on Variation in Social Insects The 



social insects (ants, bees, wasps and termites) because of the 

 differentiation of their populations into "castes," distinguish- 

 able from one another in somatic characters, present a whole 

 series of interesting problems in variation, heredity and morpho- 

 genesis. These animals afford very alluring material with which 

 to undertake biometrieal study of various problems within the 

 fields mentioned. It is a matter of comparative ease to get rela- 

 tively large numbers of individuals. The firm exoskeleton 

 makes measurement, and the preservation of material unchanged 

 for future measurement, comparatively easy. Finally, in addi- 

 tion to the wide variety of somatic structure to be found in the 

 several castes, the relation of these castes to sexual and asexual 

 modes of reproduction also adds to the intrinsic biological 

 interest and usefulness of the material for the study of general 

 problems. 



In view of these considerations it is somewhat surprising that 

 more biometric work has not been done with the social insects as 

 material. So far as the writer is aware there has as yet been 

 but one quantitative study of variation in ants, that of Kellogg 

 and Bell (10). With bees the case is somewhat better. Here 

 we have, besides the earlier work of Koschewnikow (11, 12) and 

 Bachmetjew (1, 2, 3, 4, 5 and 6) the careful quantitative studies 

 of Casteel and Phillips (7), Kellogg and Bell (loc. cit.) and 

 Kellogg (9). Miss Entemann's (8) study of variation in the 

 coloration of Polistts. which was quantitative in character, was 

 the only study of the kind on wasps before 1907. 



During the last two years two papers dealing with variation 

 in wasps have been published from Pearson's Biometric Labora- 

 tory. The first of these, by Wright, Lee and Pearson (16), 

 deals with the results of a study of the variation exhibited by 

 the individuals of the several castes (queens, drones and 

 workers) taken from a single nest of Vrspa vulgaris. From the 

 material contained in this nest it was possible to get measure- 

 ments of 129 queens, 130 drones and 129 workers. The length 

 and greatest breadth of each wing were measured, as well as 

 the dimensions of various "cells" marked off by the wing veins. 

 Altogether seven absolute measurements were made and from 

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