n. WKSTKR^ 0\ KOTfFKIJS. 157 



those of p. citrina. There are two teeth in each ramiis of the 

 trophi. The viscera present no peculiarity requiring notice. 

 The "reproduction is viviparous. They vary much in size, but 

 average ^^'oin. in length. Habitat : Commensal on Asellus 

 vulgaris from Putney, Wandsworth, and Epping Forest. 



Stephanoceros Eichornii: The Male. 



Although I imagine every member of this Club is acquainted 

 with the handsome rotifer Stephanoceros, and although it has 

 been known since 1761, marvellous to relate, there is no record 

 that anyone has seen the male. Thanks to Mr. Hood, of 

 Dundee, I have recently had an opportunity of doing so, and, 

 though of course all credit for the discover}^ is due to Mr. Hood, 

 who, it seems, found and hatched the male eggs last year and 

 sent specimens with descriptions and drawings of the male to 

 the Glasgow Microscopical Society, so far as I can learn nothing 

 has been published, and I deem the matter of sufficient interest 

 to bring before you. It was in April that Mr. Hood sent me 

 some Stephanoceros, some of which carried male eggs. He told 

 me that he had been unable to find these luale eggs after May 

 last year, but being on the look-out for them found them again 

 in April this year. I have met with but few Stephanoceros 

 this year, and have looked in vain for the male eggs, the season 

 being probably past ; with those sent me by Mr. Hood, however, 

 I was very fortunate, for I was able to keep them until the 

 males appeared. These male eggs were more numerous and 

 only about half the size of the ordinary female (partheno- 

 genetic) ova, each female carrying upwards of a dozen of them 

 within the body. Some I measured were about 3-5^in. in 

 diameter. They were laid in batches of three or four, some 

 two or three hours before the young males emerged from them ; 

 I could see decided movement of some of the embrj'os inside 

 the body of the female before the eggs were laid, but in no one 

 instance did I observe a male born alive. On the contrary I 

 almost invariably found the empty shell from which the young 

 had escaped. After birth the young males, measuring about 

 ^-^-^in., were within the tube, and from it I distinctly saw two or 

 three of them bore their way out through the side, leaving in 

 one case a hole with ragged edges. This process took them six 

 or eight hours. The appearance of the male is much like that 



JouRN. Q. M. C, Series II., No. 32 11 



