130 H. JAMES-CLARK ON THE ANATOMY, ETC., OF TRICIIODINA. 



of the feces. The velum (f,f l ) is only partially expanded. From the position of the animal the basal cilia (</) 

 arc exposed at full length. The hooks and radii of the adherent apparatus (/*) are but dimly seen through the cor- 

 rugated walls of the body. From its peculiar position in this view the vestibule is seen through the open mouth (/«). 

 The moniliform nucleus (n) is seen in the extreme distance, its right (n) and left ends are foreshortened, and appear 

 as two very conspicuous, dark yellow, oval spots, easily seen even with a low magnifying power. 650 diam. 



Fig. 13. An end view of the anterior face, looking directly into the cupuliform disc (c 3 ), and through its walls 

 upon the various organs. The ventral region corresponds to the lower side of the figure. The anus (a) appears 

 as a faint slit on the right border of the vestibule (v). The vibratory crown (b) commences abruptly on the right 

 (V) side, and appears clearly defined as a spiral just within the peristome (d l ), and equally well marked where it 



iiLM.m v'V "° ■'"•" — v" /' r — <r~/i v , 



and the nail-shaped, transverse piece (t 1 , v) are united at the angle by a triangular web («'). The mechanical con- 

 trivance for the sliding of these pieces upon and between each other is too obvious to need any comment. 

 2400 diam. 



Cambridge, Mass., October, 18G5. 



Published February, 18G6. 



