No. 512] MALE CRAYFISH WITH FEMALE ORGANS 465 



as if to lead to ovaries, but with no internal connections 

 and no discoverable use. These sham openings stand 

 in the proper place for the oviduct openings of a female. 



A review of the literature fails to show any abnormal 

 crayfish with just these combinations of male and female 

 characters; in fact, as before stated, most of the known 

 cases are females with some male features. Kecorded 

 abnormalities of crayfishes include the cases of repetition 

 of parts in one sex and the cases of mixtures of traits of 

 two sexes. The former have been brought together by 

 Bateson in " Materials for the Study of Variation. Mac 

 millan, 1894, the latter by Hay in < < Instances of Her- 

 maphroditism in ( 'rayfishes." Smithsonian Miscellaneous 

 Collections, 1905. 



In his monograph on the crayfishes of Pennsylvana Ort- 

 mann has recently described five additional cases in Cam- 

 barns, in which the external sex organs are more or less 

 mixed and in part defective. 



Bateson found that in 586 females of Astacus furiatilis 

 there were 23 abnormal cases. In these, besides the usual 

 openings upon the bases of antepenultimate legs, there 

 were one or two similar openings upon the penultimate, 

 the ultimate or even upon all; making a maximum of 

 three pairs of openings. Moreover, the oviducts gen- 

 erally branched so that more than one pair of oviduct 

 openings might be functional, but in other cases the 

 extra openings might end blindly and be of no use. Of 

 714 males onry one was abnormal and that presented 

 not a duplication, but a suppression of organs, having 



the sperm duct of that ^ide hung blindly" in the body 



A real case of duplication of sexual characters in a male 

 crayfish was recorded, in a rather inaccessible publication, 

 the Indiana University Bulletin, by W. J. Moenkhaus, 

 in 1903. He found in Cambarus viridis a male that had 

 in addition to the usual first and second male limbs of the 

 abdomen the third pair modified to exactly resemble the 



