CASE OF SAICCLNA VENTRICULI. 35U 



their angles only, as in the baccillaiiau geueitL It also 

 explams wliy 1 could never detect mure than four so uuited. 

 It may account for the circumstance that the Sakci^.k were 

 found grouped as it were in colonies, in certain portions of 

 the ropy liuid, some di-ops containing numbers of them, others 

 none at all. 



Such is the structui'e, mode of reproduction and of de- 

 velopment, of this species of Sakcina, 



In tracing these out, it cannot but have been observed how 

 beautiful is the symmetry of all the arrangements — how the 

 parts of the individual are aiTanged in the S(|uare — how these 

 parts increase in numbers in a geometrical progi-ession — 1, 4, 

 IG, 64, 256, — and lastly, how the species propagates according 

 to the same law, 4 in the firet genemtion, 16 in the second, 

 G4 in the third, 256 in the fourth, 1024 in the fifth, and so on 

 with a rapidity peculiar to such a series of uiuubere. 



Is Sarcina an animal or a vegetable? is it one of the 

 infusorial Tolygastrica, or a minute Alga ? In order to give 

 a satisfactory' answer to tliis question, it becomes necessary to 

 analyse the groups to wliich S^vkcina is most closely allied. 



Tutting out of view for the present the Fkagillarle, Dia- 

 TOMACLE, and other gonioid organisms, the animal or vegetable 

 nature of which is yet a matter of doubt, I shall proceed to 

 MiiUer's genus Gonium, the genus of all othoi-s to which 

 Sarcina has the greatest ailinity. 



The genus Gonium consists of composite polygastric ani- 

 malcules, each corpuscle of the whole animal having, accorduig 

 to Ehrenberg, the organisation of a monad, oral appendages, 

 visceral sacs, etc. Ehrenberg does not enumerate eye-points 

 among the chariicters of the family to which the GoNll'.MS 

 belong (Volvocin.e). Without coming to any decision as to 

 whether the red points on certain species of GoxiUM be really 

 eye-points, or mivoly optical illusions, T may state at once, 



* It may bo well to suiio, that tlie red dots do iiji n>iK.ar in nil the species. 



