No. :>12] MALE CRAYFISH 11777/ FEMALE ORGANS 4G3 



no sign of any female organ, the sperm receptacle, an- 

 terior to it. 



To these male external features there were added the 

 two female openings on the antepenultimate legs. On 

 the right the basal segment of the leg bore a well formed 

 normal female orifice, that is, a soft, round, dopressable 

 area, or operculum. This opened along the median edge 



shell. On the left the opercular area was perhaps some- 

 line which opened as a mouth, and the curved bounds 

 were more vague. The hard rim was thicker, apparently 

 by the amount that the straight mouth should have been 

 curved to make the normal contour. 



On dissection the internal organs were found to be 

 entirely those of a male, for the above female openings 

 had no connection with the interior and there were no 

 oviducts nor ovaries. On the right the operculum, when 



a needle point but appeared to end blindly as a mere thin 

 chitinous continuation of the shell inwards. This pocket 

 was flat. The mouth was a little more than 1 mm. long 

 and the pocket slightly shorter than the mouth, on the 

 right side. On the left the mouth slit led into a pocket 

 of less extent. 



The essential internal organs of this animal were the 

 testis and the two efferent ducts. The testis \va- a 



anterior lobes about 2 mm. long rising upwards in front 

 of the heart. Besides this well-developed part the testis 

 was continued back over the intestine as a short minute 

 membranous thread and forward between the stomach 

 and the hepato-pancreas as a clear tubular membrane, 

 or sterile part of the testis about 2 mm long, from the 

 right and from the left lobe. 



Where the right and left lobes joined the median lobe 

 the different duct sprang out each side and, passing back 

 alongside of the median lobe some 3 mm., went away at 



