296 Mr. H. M. Bernard on 



XL. — Hermaphroditism among the Apodidse. 

 By H. M. Bernard, M.A. Cantab., F.L.S., F.Z.S. 



[Plates XI. & XII.] 



In 1890 I published a preliminary notice in the ' Jenaische 

 Zeitschrift ' * announcing that in several specimens of a small 

 species or variety of Lepidurus from East Spitzbergen the 

 posterior tip of the genital gland on each side was filled with 

 sperm-cells, and that that representative of the family was 

 therefore hermaphrodite. 



By the kindness of Canon Norman and Prof. Mobius I was 

 then enabled to examine representatives of three other species, 

 viz. Lepidurus glacialis, Lepidurus productus, and A pus 

 cancriformis. One of each of these was sectioned with the 

 sole object of ascertaining whether they were also herma- 

 phrodites. In each case the specimens examined showed in 

 some part or other the same conversion of epithelial cells of 

 the genital gland into the minute clear cells which I believed 

 and still believe to be sperm-cells f. That representatives of 

 four different types of Apodida? from different parts of the 

 world should show hermaphrodite conditions would be almost 

 too marvellous a coincidence, unless hermaphroditism were 

 under certain circumstances the rule, at least in those members 

 of the family. 



Dr. Benham, in his note on a male of Apus cancriformis in 

 the February issue of this Magazine, takes me somewhat 

 severely to task for having let four years go by without 

 having published any detailed account of these hermaphrodite 

 specimens. Most people will, however, readily admit that 

 this delay was justifiable, nay, almost necessary, under the 

 circumstances ; indeed, I should hesitate before publishing 

 this paper if I had not become convinced that the herma- 

 phrodite condition is, after all, not that most commonly found 

 in these animals. 



In the first place, none of the specimens show clearly the 

 method of formation of the assumed sperm-cells ; it was 

 therefore necessary to obtain better preserved material. It 

 was some time before, through the kindness of Prof. Bieder- 

 mann, I obtained well-preserved specimens of Apus cancri- 

 formis^ Lepidurus productus, and Branchipus stagnalis. 

 The new material, however, when examined showed none of 



* Band xxv. p. 337. 



t ' Nature,' vol. xliii. 1891, p. 343. 



