546 PLANKTON OF THE SYDNEY WATER-SUPPLY, 



1-esiiIts, otherwise one of the others. Cf. Schilling, Siissw. 

 Peridineen, T. iii., f .1,9,16,17,18. 



VERMES. 



Anguillula FLuviATiLis Miiller. 



In large specimens, especially when dead, the cuticle may 

 sometimes be observed to be transversely striate. The striae 

 are fine and very faint. Closer investigation shows them to 

 be composed of rows of minute puncta, which, like those 

 forming the striae in the infusoria, seem to be caused by some 

 differentiation within the membrane. 



ROTATORIA. 



Ltndia torulosa Dujardin. (PI. Ivii., f.9). 



Found in the pond formed by the washing of the filter- 

 screens, in company with Cophens spicahis, of which it seems 

 to be the outgrowth. The toes are turned back over the body, 

 and are quite useless; the creature moves like a worm. On 

 the hindmost segment is a pair of the same processes, which 

 give the name to Copheiis spicatus; and, at iri'egular inter- 

 vals down the sides, are short fusiform spine-like processes. 

 They seem too regularly placed to be fungous growths, but 

 do not appear to penetrate the epidermis. The red spot was 

 large and cup-shaped. It is undoubtedly a gland connected 

 with the circulatory system. At intervals of, say, one minute, 

 a pink flush would appear in the vessel surrounding it ; and 

 that this was caused by an emanation from the red gland, 

 was evident, since, on more than one occasion, I observed 

 minute grains of its substance to break off from the thin edge 

 of the cup and float away in the lymph, dissolving as they 

 went, with the production of the same pink coloiiration. 



INFUSORIA. 



Trachelomonar caudata (Ehr.) Stein, var. eleoantissima 

 (G. S. West) mihi. 

 Long. 38; lat 9 /x. (PI. Ivii., f.ll). 



