OF THE CRYPTOMONADINA. 509 



C. duhia. — Quite flattened, elliptical, j sXH^di to Cryptoglenapigra,C.c^rulesce7iSy 

 not rounded anteriorly ; of a clear green and, in a less degree, to C. conica of 



colour, with a hyaline central band, 

 and, in most instances, a red stigma. 

 Movement rather quick; the filament 

 not seen. 1-1900" to 1-1400". It is 



Ehrenberg 



C. urceolaris (Smarda). — Belongs, by 

 reason of its firm testa, to the Theca- 

 monadina. 



Genus OPHIDOMONAS. — Body filiform ; eye-speck absent ; lorica smooth, 

 obtuse, and tubnlai' with a single filament ; self- division transverse and com- 

 plete ; internal vacuoles numerous. Its extremely small transverse diameter 

 is the great impediment to a better acquaintance with this being. (It has not 

 been figured.) 



Ophidomonas Jenensis. — Very thin, 

 curved spirally, and equally obtuse at 

 both extremities; colour olive-brown; 

 motion brisk. In well-water. 1-570". 



0. sangninea, — Very slender, the in- 

 terspaces between the vacuoles filled 

 with a red colour. 1-576". In brackish 

 water. 



Genus PBOROCENTRUM (XVIII. 30).— Lorica resembUng a Httle box 

 {xirceolus), smooth, pointed at the anterior extremity ; eye-speck absent ; pro- 

 boscis filiform ; vacuoles numerous. Self- division has not been observed. " It 

 is worthy of remark," says Ehrenberg, " that the only species of this genus 

 with which we are acquainted [i. e. in 1838] belong to the luminous crea- 

 tures of the sea, which, perhaps from some peculiar organic relation or con- 

 dition, yet unknowTi to us, are instrumental in producing that curious and 

 certainly vital phenomenon usually termed phosphorescence." It may be 

 further noticed, that all the luminous Infusoria of the sea, hitherto discovered, 

 are characterized as being of the same yellowish waxy colour as the best- 

 known species of this genus — P. micmis ; and it is probable that this condition 

 is immediately connected with the interesting j)henomenon in question. 



Peobocentiiuim micans. — Oval and 

 compressed, attenuated posteriorly, but 

 dilated and pointed anteriorly ; colom' of 

 yellow wax. In sea-water. (x"\T:n. 30). 

 Two figm-es, magnified 300 diameters; 

 the first is a side view, the latter a back 

 view ; the filament in the foi-mer indi- 



cates the position of the supposed 

 mouth. 1-430". 



P. viritlis. — Ovate, suborbicular, tur- 

 gid ; posterior end rounded ; anterior 

 shortly pointed ; colour green, 1-1100". 

 In the Baltic. 



Genus LAGE:N"ELLA (XVIII. 31).— Distinguished from other loricated 

 monads by the lorica being extended anteriorly, or flask-shaped. The lorica 

 is perfectly distinct, and crystalline. Within are the bright-red speck and 

 green granules. (Vide Cryptomonas LageneUa, p. 508, and ChonemonaSf 

 Perty, p. 513.) 



Lagenella euchlora (xviii. 31). — I crj^stalline ; colour green. Amongst 

 Oval, neck short and truncated ; lorica | Confervse. 1-1200". 



Genus CBYPTOGLENA (XVIII. 32).— Lorica open, in the form of a shield 

 (scutellum), folded or roUed inwardly at the sides, and without a projecting 

 neck. Eye-speck distinct ; granules green in aU the species. La C. conica 

 two oval greyish masses are seen in the centre, and also two filaments. Self- 

 division not observed. These characters, given by Ehrenberg, are valueless to 

 distinguish Gryptoglena from other Crj-ptomonadina, or from Chlamydococcus. 

 The scuteUar form of the lorica is an error ; for it forms a complete investment, 

 intennipted only at the point where it gives exit to the filaments. The red 

 eye- speck is no distinction, as so often remarked ; and the absence of a neck- 

 like extension of the lorica is seen in Cryptomonas, Chlamydococcus, and other 

 genera. Carter describes one species with four filaments. We unite with 

 Dujardin in rejecting this as an independent genus. 



