12 Transactions. — Zoology. 



Length of animalcule, including pedicle, ^o inch = 100 fi. 



Saville Kent makes no mention of any divisions on the 

 peristome-edge of T. fluviatile, and his description of that species 

 is by no means full. In T. semiciliatum , Sterki, he mentions 

 both a " cleft " oral region and a " lip- or tongue-like organ." 

 But he seems doubtful whether Sterki's form is not really the 

 same as Stein's. The main character of T. semiciliatum, if quite 

 certain, is the pectinate form of the adoral cilia. This is not 

 noticeable in our New Zealand animalcule. On the whole, it 

 seems possible that all the freshwater species of this genus may 

 be identical, and the present is only offered as a " variety," 

 subject to future revision. No species of Tintinnidium seems to 

 have been reported anywhere else since the publication of Kent's 

 monograph. 



Order. Peeitkicha. 



Genus Strombidium. 



Strombidium intermedin) a, sp. nov. Plate III., fig. 17, ((, b, c. 



Animalcules free-swimming, ovoid, with a short posterior 

 prolongation ; colour whitish, with enclosed granules ; about 

 one and a half times longer than broad ; anterior border rounded, 

 posterior projection tapering nearly to a point. On the anterior 

 portion is a ring of long, fine cilia, which in end-view (fig. 17, b) 

 are seen to be disposed spirally. Contractile vesicle single, 

 close to the posterior projection. Nucleus elongate-oval, placed 

 diagonally below the ring of cilia. No cilia on any part except 

 in the ring. Motion excessively rapid, jerking, and difficult to 

 follow. 



An example observed of reproduction by fission is shown in 

 fig. 17, c; the two bodies are at right angles to each other. 



Length, -^j inch = 38'5 /x. 



Otaki, W. M. Maskell. 



Intermediate between S. claparedii, Kent, and S. gyrans, 

 Stokes. * 



Genus Mesodinium. 



Mesodinium phialinum, sp. nov. Plate III., fig. 18, n,b. 



Animalcules free-swimming, shaped like a small jar or bottle, 

 divided unequally by a ring, at tbo base of which are a number 

 of longish, straight, fine cilia, which in end-view (fig. 18, 6) 

 are seen to be disposed as rays, not spirally ; above the ring the 

 body is prolonged in a sub-conical projection, deeply concave at 

 the top. Contractile vesicle single, spherical, placed posteriorly. 

 Nucleus small, spherical, sub-central. Motion excessively rapid, 

 rotatory, varied by violent leaps and jerkings. 



Length, including projection, j^ v iuch = 17'8 ft. 



* " Quart. Journ. Hoy. Micros. Soc," Feb., 1887, p. 37. 



