No. 512] MALE CRAYFISH WITH FEMALE ORGANS 467 



pseudo-female opening; while if there was an ovary the 

 oviducts went to the normal openings and the extra male 

 openings were of no use, though here again the ovary 

 sent out a duct towards the useless male openings. 



The extra openings, however, Lonnberg found to be 

 shams, or closed openings, yet they look like the openings 

 of the opposite sex. 



This state of things, the perfect male or female with 

 sham openings and pseudo-ducts of the opposite sex, 

 seems to be the usual, if not the only, condition found in 

 many species of the genus Pakistanis, to judge from all 

 the specimens that have been studied. The relationship 

 between Parastacus and Cambarus is, however, believed 

 to be so very remote that one can not suppose the present 

 case of abnormality in a species of Cambarus has any 

 genetic connection with what seems to be the rule in 

 many, but not all, species of Parastacus. 



The other recorded gynandromorphs are one specimen 

 of Astacus and fourteen of Cambarus, and all except one 

 are females that have some male characters added. 

 The superfluous male characters are sometimes but the 

 modification of the first abdominal I i ml is to resemble those 

 of the female, in others both these and the following limbs 

 are just like the male limbs. In one the male attach- 

 ment hooks, and the male openings and even the hirsute 

 spine posterior to the somite of the sperm receptacle, 

 that is, all the external characters of the male, are 

 present along with normal ovary and oviduct. 



This last was the most hermaphroditic of all known 

 crayfishes. It was the female Cambarus affinis, 106 mm. 

 long, described by Hay. This seemed externally a male 

 and attempted conjugation with a female, having a good 

 set of male external organs. But internally it had a 

 large ovary with nearly mature eggs and two perfect ovi- 

 ducts. The specimen was thus deficient in lacking the 

 sperm receptacle that a female of this kind of crayfish 

 should have in order to get the eggs fertilized. In addi- 

 tion to the ovary there was a small testis, on the right, 



