112 PROF. G. S. WEST ON FRESinVATER RHIZOPODS 



much attenuated, and almost always branclied. Except for their 

 perfectly smooth exterior and absence of granules, they are very 

 like those present in the genus VampyreJla. 



This species is a voracious feeder, and many of the individuals 

 were gorged with Desmids. The protoplasm contained no green 

 colouring-matter, the chlorophyll of the Desmids disappeariug 

 very soon after ingestion. The pseudopodia were frequently 

 entirely retracted, the animals then remaining in a quiescent 

 state for a long time (fig. 18). In this state they much resembled 

 the quiescent stages of Vaonpyrella pedata, Klein, but could be 

 distinguished by the numerous vacuoles and the absence of the 

 red pigment. 



Slight stimulation of the animals, either mechanical or with 

 reagents, caused a contraction of the pseudopodia, so that they 

 became undulated, as shown iu fig. 19. 



I have previously pointed out that Seterophrys varians, 

 Schulze, is identical with Ilelioplirys variabilis, Greeff, and that 

 the animals in question do not belong to Archer's genus Setero- 

 phrys. I am now quite convinced that both are forms of 

 Cienkovvski's Nuclearia delicatula, and are E-hizopods which 

 should be placed in the order Vampyrellida. 



Genus Vampyeella, CienJcoioshi. 



2. Vamptkella lateeitia, Leidy, FresJiw. BTiiz. iV. Amer. 

 1879, p. 253, pi. 45. figs. 10-16. — Amoeba lateritia, Fresenius, 

 1856-8. — Vampyrella Spirogyrse, CienJc. in Archiv fur mihr. 

 Anat. i. 1865, p. 218, pis. 12-13. figs. 44-56. 



Sal. "West of Tarbert, Harris, Outer Hebrides. 



Numerous examples were observed amongst various algae, but 

 all of them were sluggish, and none were observed feeding. 



Order Amcebcea. 

 Family L o b o s a. 



Genus Pelomyxa, Greeff. 



3. Pelomyxa palusteis, Greeff, in ArcTiiv fur mihr. Anat. x. 

 1870, pp. 51-72, pis. 3^. 



Sah. Near Tarbert, Harris, Outer Hebrides. 



Not uncommon in boggy pools amongst submerged Sphagnum. 



