TORQUATELLA TYPTCA. 273 



these swarming ciliate Infusoria, I observed the speci- 

 mens drawn in PI. XII, figs. 1 — 5. They were exceed- 

 ingly active, and had to be examined both in the living con- 

 dition and after their movements had been arrested by the 

 administration of a trace of Osmic Acid, in order to ascertain 

 definitely their characteristics. Though having the appear- 

 ance and habit of a ciliate Infusorian, this form — for which I 

 propose the name Torquatella — does not possess any cilia at 

 all. The body is oblong, and has the same mobility as that 

 exhibited by most of the Ciliata. At the anterior extremity 

 is placed the mouth, overhung by a capitular prominence, or 

 upper lip (c c), as is not unfrequent in the group. There is 

 a definite cuticular membrane to the body-sac, but, contrary 

 to what occurs in most ciliate Infusoria, this does not transmit 

 any delicate processes of vibratile protoplasm. There is not 

 even a ring of such cilia surrounding the oral region and 

 capitular prominence, as in Vorticellidce , but in its place a 

 complete delicate bell-like prolongation of the body wall, 

 which may well be compared to an Elizabethan frill or 

 plicated collar. This large collar quite overhangs the 

 cephalic region, and reaches in front of it. It is no mere 

 cuticular expansion, but has protoplasmic characteristics, 

 being continually in a state of vibration, alternately closing 

 up and expanding with a twisting movement, and exhibiting 

 the same rapidity and regularity in this movement as do a 

 series of cilia in a similar position. In fact, the movements 

 of this collar may be best understood by comparing them to 

 the movement of a series of cilia united to one another along 

 their length by delicate membrane. In figs. 1 — 3 the collar 

 is seen in a quiescent condition, when it exhibits obliquely- 

 directed folds. In figs. 4 and 5 it is seen at the other 

 extremity of the stroke, that is to say, expanded. 



The vibrating collar of Torquatella functions as an organ 

 of locomotion, and also serves to bring food-particles into the 

 region of the mouth. In fig. 4, a Torquatella is sketched as 

 seen in active progression. Locomotion is efiected in the an- 

 terior direction, and consequently the cup or collar becomes 

 fully expanded, its active " beat " being probably dowuAvards 

 and backwards. When the beat is sufficiently vigorous, the 

 motion produced tends to prevent the collar, in its passive 

 recoil, from gathering up round the mouth. But when the 

 stroke of the collar (comparable to the stroke of a cilium) is 

 less powerful, the organism remains unchanged in position, 

 and the collar recoils to its full extent after each beat, gather- 

 ing itself in folds round the oral region. The tendency of 

 this less violent movement will be to bring a series of waves 



