as Infusoria flagellata. 199 



but yet had neither the sigmoid curve of the latter nor its 

 stout and rigid aspect, but was much more delicate, and in 

 fact still exhibited a slight tremulous motion. The two con- 

 tractile vesicles {cv) of each body were as distinct as those of 

 the adult, and had the same proportionate size and relative 

 position. 



In a very few minutes the two resultants were totally sepa- 

 rated and divergent from each other at a sharp angle ; and in 

 less than half an hour after the last time noted, they had as- 

 sumed the proportions of the other members of the colony. 

 Shortly after the investigation of the phase just described, the 

 last stages of self-division of another body, belonging to the 

 same colony, were observed ; and thus the group, which within 

 two hours before consisted of five individuals, was increased to 

 eight (fig. 7). It seems to be a rare occurrence that so many 

 bodies remain long together, since it very seldom happens that 

 more than four or five (fig. 8) are found in a colony ; and now 

 and then, in such instances, I have seen an individual drop off 

 and swim away. When we meet with them settled down 

 upon some point, amidst others which have scarcely any stem 

 and those which are seated on very short peduncles, it becomes 

 perfectly clear that they are there for the purpose of secreting 

 a new support from the posterior end. 



§ 7. Salpinggeca*, nov. gen. 

 Sal])ing(£,ca gracilis^ nov. sp. PI. VI. figs. 38, 39. 



The difference between this genus and Codonoeca has already 

 been pointed out. It might well be compared to a stemless 

 Codosiga (§ 6) enveloped in a sheath. I have met with three 

 quite diverse species of this genus, of which that under present 

 consideration and another {8. am/phoridium^ nov. sp., §9) are 

 freshwater denizens, and the third {8. marina, nov. sp., § 8) 

 is a marine inhabitant. 8. gracilis (figs. 38, 39) was found 

 upon only one occasion, and then in an old aquarium, which 

 could not be said to be in a perfectly healthy condition, al- 

 though its contents were by no means putrid. 



The body is yellow, and has a cylindrical shape, about four 

 times as long as broad, narrowed and rounded behind, and 

 rounded-truncate in front. Like Codosiga it bears a filmy, 

 membranous, colourless collar (^), which is attached to the 

 extreme edge of the frontal area (//•), and rises to a height 

 which is equal to two-thirds of the length of the body. The 

 outline of the collar is generally cylindrical, and truncate 

 at the distal end, but still is subjected to various degrees 

 * (ToKniy^, a trumpet ; olKta, to inhabit. 



