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THE AMERICAN NATURALIST [Vol. LIV 



A Piece of an Ovaey Present in a Male Crab 

 A normal male fiddler was opened to obtain pieces of 

 its testis. In the region where the left testis is supposed 

 to end there was found a small piece of ovary with its 

 purple eggs. These were sectioned and found to be nor- 

 mal eggs. This observation is significant in so far as it 

 shows that ovarian tissue can grow and differentiate in a 

 purely male environment. The explanation of this oc- 

 currence is not at hand. One is tempted to refer to it an 

 abnormal cell division in the testis of such a sort that the 

 chromosome combination (if such exists) to produce 

 eggs was formed, but in the complete absence of infor- 

 mation concerning the chromosome composition of the 

 male and female Crustacea, such an attempt would ap- 

 pear premature. 



Intersexes and Gynandromorphs in Crustacea 

 If it does not seem probable that the aberrant types 

 in the fiddlers, that have been described above, can be 

 safely referred to parasitism, it may not be without in- 

 terest to point out that there are many other queer cases 

 of sex mixtures in the Crustacea, that do not appear in 

 any way connected with environmental changes— or at 

 least not directly. 



Many cases of intersexes have been described in the 

 Cladocerans, in the genera Daphnia, Alona, Leptodora, 

 Sintocephalus, under the name of androgynes, gynandro- 

 morphs, intersexes, etc. (Kurz, 1873. Grochowki, 1896. 

 Woltereck, 1908. Kutner, 1908. Ashworth, 1913. Agar, 

 Banta, 1918. De la Vaulx, 1915 and 1918). The anten- 

 nae more often show modifications characteristic of both 

 sexes, but other organs are frequently involved, includ- 

 ing even the gonads. There are no indications of para- 

 sites in any of these cases, where owing to the transpar- 

 ent of the body they would be easily detected if present. 



Kutner has recorded the sporadic occurrence of inter- 

 mediate forms through 12 generations of Daphnia pulex 

 -in a line having a relatively high percentage of these 



