516 



SYSTEMATIC HISTORY OF THE INFUSORIA. 



istence, are very questionable ; for the possession of a double iorica, attributed 

 to ^yncrypta by Ehrenberg, cannot seiTe as a generic distinction from Oyges, 

 with a single Iorica, since Cohn has shown in Chlamydococcus that the pro- 

 duction of a distinct, loosely investing, and apparently second covering, is one 

 of the series of developmental phenomena in the selfsame being. The same 

 statement is true of the so-called tail which is used to separate Symira from 

 other allied forms ; for caudate beings make their appearance in the cycle of 

 existence of non-caudate : thus a caudate variety of naked " zoospore " re- 

 sembling a Bodo is represented by Cohn in his illustrations of the multiform 

 phases of Protococcus. The presence of a mouth, and the construction of the 

 envelope with one side or end open, through which the animal can protrude 

 itself at will, are statements now generally ignored. 



After excluding the inadmissible and the very doubtful genera of this 

 family of Ehrenberg, there remain only Pandorina, Gonium, Chlamydomo- 

 nas, and Volvox. To these, other natiu-ahsts add Chlamydococcus (Braun), 

 Glceococcus (Braun), Stephanosphcera (Cohn), and Stephonoma (Werneck). 

 Ehrenberg himself has added a new genus he names Trochogonium ; but, from 

 the imperfect description given, it is not possible to decide accurately whether 

 it is distinct from some of the genera instituted by other naturalists. 



Genus GYGES. — Lorica of a simple box-like form (urceolus) ; eye-speck 

 and ' tail ' absent ; filament doubtfully present ; the internal organization is 

 Httle known. Two species are mentioned by Ehrenberg, both of a green 

 colour and enclosed in a transparent lorica. 



Gyges Gramdum (Volvox Granulum, 

 M.). — Oval, or nearly globular; con- 

 tained granules of a darkish green colour. 

 Amongst Lemnas and Conferv?e. 1-1150". 



According to Cohn (on Protococcus, 

 p. 559) the encysted motile zoospore 

 (xix. 31) oi Protococcus ( Cldamydococcus) 



pluvialis is the same as this species Gyga 

 Gramdum', whilst the same zoospores di- 

 vided into two must be regarded as the 

 next species, Gyges bipartitus. 



G. bipartitus. — Crystalline, gelatinous, 

 and nearly spherical ; the superficies co- 

 lourless, but its granular contents yel- 

 lowish green ; it is sometimes seen di- 

 vided into two, at others as a simple 

 sphere. Amongst Confervas. 1-480". 



G. sanguineus. — Oval, red, inclining to 

 crimson, surroimded by a broad colour- 

 less ring representing the enveloping 

 lorica. This species was discovered by 

 Mr. Shuttleworth in the red snow which 

 fell at the Grimsel in August 1839. Its 

 motion is lively. Group 527 (x'^ii.) 

 shows several highly magnified. Found 

 with Astasia nivalis and Monas gliscens, 

 among the globules of Protococcus nivalis 

 {Ed. Phil. Journ. v., xxix.). 1-1200" to 

 1 -300' '. This is probably only the ' still ' 

 phase of Chlamydococcus pluvialis. 



M. Vogt gives a very singular account 

 of the mode of reproduction of this 

 being. He says, " It gives off" from se- 

 veral parts of its body small transparent 

 buds, apparently vesicular, and for the 



most part fiUed with granular matter. 

 As they enlarge they become gradually 

 detached ; sometimes two of equal size, 

 of which one is red and loricated, the 

 other colomiess, adhere by a very narrow 

 point of attachment, which subsequently 

 gives way, and the bud appears as an 

 Infusory animal, like what Mr. Shuttle- 

 worth has represented in his 7th and 8th 

 figures, and which approaches Pandorina 

 hyalina (Ehr.)." 



This account of the reproduction of 

 this species of Gyges is so peculiar and 

 exceptional, that the questions arise 

 whether it really is a member of this 

 genus and family, and, if it be, whether 

 the description is a correct interpretation 

 of the facts observed. 



M. Vogt adds that Gyges sanguineus 

 ought not only to be looked upon as the 

 type of a new genus, but even of a new 

 familj^, on account of its very peculiar 

 mode of reproduction. He farther de- 

 scribes a new species : — 



G. Vogtii. — Globular, containing in its 

 interior from two to five individuals, 

 enveloped by an apparently silicious 

 lorica ; colour dark red ; frequently found 

 adherent and arranged in the form of a 

 cross, also often separate. '* The small 

 individuals, probably the yomig, were 

 of a clear yellow hue. I could not ob- 

 serve the slightest motion in them." 

 — On the Animalcules of the Red Suow, 

 Bibliotheque Univ. de Geneve, May 1841. 



