JOUENAL 



OP THB 



ROYAL MICROSCOPICAL SOCIETY. 



JUNE 1902. 



TRANSACTIONS OF THE SOCIETY. 



VII. — The Genus Synchceta : 

 A Monographic Study, with Descriptions of Five New Species. 



By Charles F. Bousselet, Curator and F.R.M.S. 



(Read June 18th, 1902.) 

 Plates III. to VIII. 



Some of the members of this genus are amongst the commonest 

 Rotifers inhabiting fresh-water lakes and ponds, as well as brackish 

 tide pools and the open sea. Being also of fair size they will 

 necessarily have been amongst the Rotifers observed by the early 

 investigators with the Microscope. Pastor Eichhorn (1761) and 

 F. 0. Miiller (1786) are probably the earliest authors who have 

 left sketches that can be recognised as Rotifers belonging to this 

 genus, but the species cannot be determined. Our real knowledge 

 of these Rotifers dates from about 1831 to 1834, when Prof. 

 Ehrenberg determined four species of Synchseta : — S. pectinata, 

 tremula, oblonga, and baltica. Up to 1886, when Hudson and 

 Gosse's monograph was published, these four remained the only 

 known kinds, and in the Supplement published in 1889 only two 

 more species, S. longipes and gyrina, were added to the list. At 



EXPLANATION OF PLATE III. 



Fig. 1. — Synchseta pectinate^ Ehrbg. $ Dorsal view, x 250. 



? Dorsal view. X 375. 



The male, dorsal and side views, x 400 



9 Dorsal view. X 300. 

 The male, side view, x 450. 

 One uncus of the jaws. 



T 



