Cryptomonadina.'] infusokial animalcules. 141 



their imperfect peculiar self -division, form a compovmd body 

 {polypary, ) resembling a whorl, or cluster of berries. 



S. quaternarium. — Animalcides alternating in a group of four, of 

 which the terminal one is the most slender ; coloiu- green ; probos- 

 cides 4 to 5. Length of polj^)ary 1- 570th; of each animalcule 

 1-1 728th. 



Family.— CRYPTOMONADINA. 



The family Cryjotomonadina exhibits aU the characteristics of the 

 Monadina, (and no certain or definite ones of any other family,) they 

 ai-e besides furnished with a distinct gelatinous, membranous, or 

 hard induvium, or shell-like substance, termed a lorica, in which 

 they are more or less enclosed. Considering them as a family, their 

 organization has been determined as completely as that of the Mona- 

 dina, or even of the larger Pohjgastrica ; although something more 

 is yet to be learnt of the species indi-vidually. The lorica, or integu- 

 ment covering these creatiu'es, is of different forms ; sometimes 

 having the figure of an open shield fscutellumj, at others of a closed 

 box or a pitcher furceolusj. Locomotive organs are clearly percep- 

 tible in aU the genera, excepting, perhaps, the genus Lagenella, and 

 even in this. Dr. Werneck is of opinion that he has discerned them. 

 They consist of two delicate, filiform, and generally reti'actile pro- 

 cesses, issuing ii-om the margin of the mouth, and capable of being 

 put into very powerful rotatory motion. We shall designate them, 

 as with the Monads, proboscides. The nutritive apparatus of these 

 creatures has not yet been demonstrated by the application of coloured 

 artificial food ; but with six or seven species (nearly one-half the 

 family) internal cells have been discovered. In two genera, a sen- 

 sitive system may be presiuned to exist, from a coloured spot or eye- 

 like appearance being present at the fore part of the body. From 

 the position of this organ of vision, the dorsal line may be readily 

 conceived, so as to indicate a right and left side of the creature. 

 The individuals either self-divide simply and completely, or they do 

 not divide at aU. " It is possible," says Ehrenberg, " that the fossil 

 animalcules discovered in the flint of chalk and porphyritic forma- 

 tions, and named bj- me Pyxidicula (see Plate 12, upper figures) 

 belong to the genus Trachelomonas. 



