BY G. I. PLAVFAIR. 101 



the figure differe from both Dirujbri/on and Poteriodendron. Dinohryon petio- 

 lotum Duj. (Hist. Natur. des zoophytes Infusoires, p. 322, T.i., %. 22) has 

 nothing' to do with Poteriodendron, as the author says "animaux vert-s.'' 



Var. Abbotti (Stokes) mihi. (PI. i.. tig-. 2.). 



Cupules conieal-campanulate, rim not everted, dimensions same a-s those of 

 the type. 



Sydney Water-Supply ; Lismore (260, 290). 



Syn. Stylobryon Abbotti Stokes, Infusoria of the U.S., p. 79, PI. i., fig:. 

 12; Dinohryon sertidaria fonna, Playf.. Plankt. Syd. Water, p. 515, PI. 57, fig. 

 5; D. sertularia var. conicum, Playf., Fnv. Alg. Lismore, p. 315; Cf. Stein, I.e. 



Stokes gives a good detailed account of this form and its zooid, but his 

 figure is incorrect, as he says that the cupules are twice as long as the maximum 

 breadth (true also of Stein's and of our own) whereas in fig. 12 the proportions 

 are only 6 :5. I find the two fonns intermingled in the same .spray. 



Fam. CRASPEDOMONADACEAE. 



Genus Sphaerorc.^ Lauterborn. 



Sphaeroeca volvox Lauterl)orn. 



Coenob. diam. c.lSju,; cell. long, circa 5, lat. c. ^/u- Lismore. 



Cf. Senn, I.e.. p. 126, f. 84b (after Lauterborn). Very rare, only once 

 noted as a minute coenobium of hyaline cells radiating from a centre as in 

 Synura. The cells w-ere so small and the outlines so indistinct that even under 

 a high magnification I was unable to make out the details. Senn gives the 

 dimensions as, c°lls 8 — 12^ long, coenobium uj) to 200ju,. 



Genus S a l p i x t; o e c a Clark. 



I do noc think tiiat there is anything characteristic of the species in the 

 presence, absence or length of the petiole in this genus. Kent's figures. I.e., PU. 

 v. and vi. sjem to me to show this distinctly. PI. v., f. 20, makes it quite dear 

 also that the coenobium may simulate Petiidatum so that in the absence of the 

 zooid one cannot be distinguished from the other. 



Salpixgojx'a ampullacea (A. Hr. ) Stein. (PI. i., fig-s. 3, 4). 



Cell. long. 10, lat. 4i— 6]/^. Lismore (302). 



Syn. Chi/tridium ampullaceum, A. Braun, "On Chytridium." T. v., f. 24 — 

 27; Stein, I.e., iii., H. i., T. xi., f. 6, 7. Quantities noted on one occasion on 

 Oedogonium — rare, however, in my experience. Kent's figures of S. amphori- 

 dium, I.e., PL v., f. 2, 5, at least, should be considered as representing tliis 

 species, the long narrow tubular neck being characteristic. A minute peduncle 

 may sometimes l>e observed and is probably very tiften present when not notice- 

 able. 



Var. CORD ATA, n. var. (PI. i., fig. 5). 



Loricae corpore cordiforme nee globoso, interne acuminato, lateribus levissime 

 arcuatis. Long. 10, lat. 4i— 6J/i. Lismore (302). Cum forma typiea. 



The body of the lorica is more or lass heart-shaped, not globose, and runs to 

 a point beneath. Kent describes and figures {I.e., PI. v., fig's. 13—16), species 

 S'. amphora Kent and S. urceolata Kent, of somewhat similar shape, but with- 

 out the long neck. On Oedogonium in quantity, mixed with tlie type. 



