344 



ORDER CHOANO-FLAGELLATA. 



to the notice of the scientific world by Professor H. James-Clark,* it has been met 

 with by the author in incredible numbers coating the filaments of various confervoid 

 alo-ce and other water plants taken from numerous widely separated localities. A 

 tolerable idea of the gregarious habits of this Flagellate animalcule, as manifested 

 under favourable conditions, maybe gained by reference to PI. V. Fig. i, representing 

 the portion only of a colony attached to a single cell of one of the filamentous 

 al-^je viewed with a magnifying power of about 600 diameters. The lorica, which 

 throughout Salpingccca and the three succeeding genera furnishes as a rule the only 

 safe and reliable means of arriving at a satisfactory diagnosis of the species, is in 

 this particular instance strongly suggestive of a Florence flask, or the more familiar 

 caraffe that forms the necessary adjunct of the domestic toilet-table. With these 

 it likewise vies in its crystalline transparency, which thus freely permits a clear and 

 uninterrupted view of its living occupant. 



The contained zooid itself, whose hardened exudation has built up its crystal 

 cell, closely corresponds with that of a Codosiga or Mouosiga, but exhibits a still 

 greater amount of plasticity and tendency to alter its shape than has been observed in 

 either of those two genera. The animalcule, which after secreting its lorica lies entirely 

 free within it, occupies in its normal condition about one-half of its cavity, as repre- 

 sented at PI. V. Fig, 2, the film-like coUar and flagellate appendage projecting beyond 

 the distal expansion of the neck of the lorica. It frequently happens, however, that 

 the sarcode body occupies a considerably larger portion than one-half of the cavity of 

 its lorica, and it is under these conditions that the animalcule usually exhibits its 

 most characteristic polymorphic properties. At such times the hyaline collar 

 disappears, having been altogether withdrawn into the substance of the body ; the 

 flao-ellum is soon retracted in a similar manner, and the whole animalcule thus 

 becomes to all appearance one homogeneous mass of protoplasm. On arriving at 

 this stao-e, or even before the absorption of the flagellum, however, this little speck of 

 sarcode, apparently cramped and confined by the walls of its domicile, has com- 

 menced to protrude or bubble over, as it were, from the orifice of the lorica, the 

 sarcode thus projected exhibiting remarkably diverse contours. Figs. 5 to 7 of the 

 plate representing this species serve to illustrate the more typical modifications that 

 may be assumed under the above conditions by the extended sarcode. Fig. 5, for 

 instance, represents a phase in which, the collar being retracted, the flagellum still 

 remains intact, and projects from a lobe-like extension of the excurrent sarcode. At 

 Fio-. 7 the flagellum is entirely withdrawn, and the mass of protruding sarcode, greatly 

 increased in bulk, is separated into numerous digitate prolongations, imparting to the 

 animalcule a general aspect strongly suggestive of an example of the loricated Rhizo- 

 pod Difflugia, with its pseudopodia extended, and of which genus, had it been only 

 encountered in this stage, it might have been consistently accepted as a minute species. 

 Fio-. 6 represents a third variety of the many protean forms assumed by this animal- 

 cule and in which the projecting sarcode is split up into innumerable fine divisions 

 after the manner of the pseudopodia of the genus Gnwiia. We have in this 

 instance, probably, a phase exhibiting an abnormal disintegration of the hyaline 

 coflar previous to its complete absorption, and corresponding in kind, though exceeding 

 it in degree, to that one reported by C. Robin of Codosiga botrytis, in which, as already 

 related, the collar was replaced by four processes resembling setae. The import 

 of the foregoing singular modification of the sarcode of Salpiugceca aiiipJioriditun 

 does not however culminate in its mimetic resemblance to certain ordinary Rhizo- 

 pods. There is undoubtedly correlated with this phenomenon one of the most 

 important phases of the animalcule's reproductive functions. It has indeed been 

 ascertained by repeated observation on the part of the present author, that the 

 redundant mass of sarcode extruded from the interior of the lorica under the 

 various forms described, is ultimately severed from the parent mass, and after a 

 short lease of Uberty reattaches itself and becomes developed into a collared zooid 

 resembling that from whence it sprang. The parent animalcule, after this budding 

 or practically transverse fission process, diminished consitlerably in size, assumes its 



* ' Memoirs of the Boston Society of Natural History,' vol, i., 1S6S. 



