Whiting: Heredity in Wasps 



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26s 



FEMALES WITH MORE THAN NORMAL NUMBER OF APPENDAGES 



The female normally has, in addition to the sting, two sensory gonapophyses. Additional 

 appendages of similar nature may occur, however, as shown in Figure a, or one of those normally 

 present may be bifurcated or forked as shown in Fig b (about Xll.) (Fig. 23.) 



hence arising from fertilized eggs. 

 These anomalous blacks have been 

 tested with virgin orange females and 

 have usually proved sterile. Only male 

 offspring of normal matroclinous char- 

 acter result, as from virgin females. In 

 a few cases, however, females have been 

 produced although in very small num- 

 bers. These females may bear the 

 black eye color of the patroclinous male 

 parent or they may have orange eyes 

 showing their father to be a mosaic. 

 Further evidence of the mosaic charac- 

 ter of some of the patroclinous males 

 is now being accumulated by crossing 

 orange females with defective veins by 

 type males. The resulting orange male 

 offspring have defective veins thus 

 showing both maternal characters, 

 while the anamolous blacks have for 

 the most part the normal paternal 

 wings. In a few cases, however, they 

 show the maternal defect in the wings 

 combined with the paternal black eye 

 color. In a single case an orange-eyed 

 brother of anomalous black males 

 bred like a black showing that although 

 his eyes were of maternal origin his 

 gonads were paternal. A very few 

 gynandromorphs or sex mosaics have 

 likewise been produced. 



A survey of experimental and cy- 

 tological work done on Hymenoptera 

 shows that with the possible but doubt- 

 ful exception of certain of the saw 



flies, the lowest family of the order, 

 males have the reduced chromosome 

 number, while females, whether pro- 

 duced sexually or parthenogenetically 

 are diploid. The mixed and more or 

 less patroclinous drones of the honey 

 bee derived from crosses of black 

 German or French and yellow Italian 

 races may, as in Hadrobracon, be 

 haploid mosaics in which certain parts 

 of the body contain only maternal 

 nuclei, while in other parts the nuclei 

 are derived from the sperm. It may 

 be supposed that the unfertilized 

 reduced egg nucleus commences par- 

 thenogenetic cleavage producing nuclei 

 or maternal blastomeres without capa- 

 city for fusion with the male pronu- 

 cleus. The latter then undergoes 

 cleavage forming paternal blastomeres. 

 The definitive embryo is therefore 

 formed in part from paternal, in part 

 from maternal blastomeres. Gynan- 

 dromorphism may be tentatively ex- 

 plained by assuming fusion of paternal 

 with maternal nuclei to form the female 

 parts of the embryo. 



NON-GENETIC ABNORMALITIES 

 OF GROWTH 



Hadrobracon has proved to be sub- 

 ject to numerous deformities of growth 

 some of which are illustrated in accom- 

 panying photographs. Legs have 

 shown peculiar swellings and bendings 



