168 MICROSCOPIC FAUNA. 



Lophrypoda. Ostracoda. 



Cypris. 15 sp. 



Can don a. 5 sp. 

 Branchiopoda. Cladocera. 

 DapJuiia. 



Chydoriis. 



ROTIFERA. 



Ord. Peritricha. Fam. Vorticellidce. 



Episiylis. sp. 20. 



Carchesiiim. sp. 7. 



CotJiiirina. sp. 18. 



Vortkella. sp. 61. 



Fam., Urceolaridce, Four Genera. 



Genus, Trichodina^ 5 sp. 



Species Z! petidicuhis. 

 Cilia-rayed. 



Floscidaria. StepJianoceros. 

 Ciliary disk, continuous. 



Melicerta ri7igeus. M. tyro. M. Iwinias. 



CEcistes. 

 Ciliary disk, double. 



Rot. vulgaris. 

 Ciliary disk, multiple. 



Brachiofuis pal a. 

 Lophopus. 



Such are the contents of a bottle cast carefully amongst the 

 weeds of the canal ; these contents might easily be added to, if 

 the search was more closely made and the searcher more untiring. 

 But even these present sufficient variety, and furnish abundance of 

 interest. It will be observed that in this list, there is nothing really 

 rare or strange. All these fauna are familiar to most microscopists, 

 so that what I have now to speak about will be nothing more than a 

 travelling over old ground, and repeating a well-worn and well- 

 thumbed lesson. 



I will first take a well-known genus of the fresh-water Polype., 

 of the family Hydride. 



