AMONG SIMPLE SAECODE ORGANISMS. 399 



To the same group of freshwater filiferous Thalamopliora belong 

 the species referable to Claparede and Lacbmann's genus Plagio- 

 phrys. Hertwig and Lesser correct and supplement the descrip- 

 tion of this genus given by Claparede and Lachmann, who, re- 

 garding it as destitute of shell, place it in their family of the Acti- 

 nophryidse. It is really provided with a delicate membranous 

 flexible test, which is thrown into folds by the various movements 

 of the body. According to Hertwig and Lessor's amended 

 description, the Plagiophryses are monothalamic Thalamophora 

 with definite and but slightly varying body-forms and with 

 branched filiform pseudopodia which seldom or never anas- 

 tomose. They have a delicate test, which lies close upon the 

 body, participates in the slight changes of shape of the included 

 protoplasm by becoming thrown into folds, and is provided with 

 a single orifice for the passage of the pseudopodia. Two new 

 species are described. 



Hertwig and Lesser* have raised the Arcella hyalina of Ehren- 

 berg into a new genus under the name of Lecythium. This rhizo- 

 pod has been further examined by Cienkowski f. 



Its nearly spherical membranous shell is of a crystal clearness, 

 and is closely applied to the protoplasm. The pseudopodial orifice, 

 which is borne by a very short neck, is situated a little to one side, 

 so that the shell possesses a slightly bilateral symmetry. The pro- 

 toplasm presents a posterior almost perfectly homogeneous divi- 

 sion in which is imbedded the large spherical nucleus with its 

 nucleolus, and an anterior granular division rich in vacuoles, 

 which show no pulsation. It is especially distinguished by its 

 greatly developed pseudopodia-emitting mass of protoplasm {JPseu- 

 dopodienplatte) which pours itself out of the shell-orifice in order 

 to send forth strong radiating and rarely anastomosing pseudo- 

 podia, and which either forms an amorphous mass or envelopes the 

 entire body with a pseudopodial mantle. 



Lecythium usually forms colonies in grape-like clusters with a 

 common pseudopodial plate ; the colonies result from a longitu- 

 dinal division of the rhizopod. 



Nearly allied to Lecythium is a monothalamic rhizopod to 

 which Cienkowski gives the name Chlamydophrys stercorea, and 

 which he frequently met with during his researches among fungi 



* " TJeber Rhizopoden," &c. Arch. f. mikr. Anat. Band x. Supplement-Heft, 

 t " Ueber einige Rhizopoden und verwandte Organismen," Arch. f. mikr. 

 Anat. 1875. 



