THE LEECHES OF JAPAN. 897 
simple in structure, I have not been able to distinguish with 
certainty more than four rows, but think it not improbable 
Fic. 2.—Section of one of tlhe marginal sense-bulbs on the ventral side of 
Clepsine. The nerve and the large clear cells are not represented. 
Fic. 3.—Diagrammatic section of one of the inner lateral sense-bulbs of the 
dorsal side of Clepsine. 
e. Cuticle. ep. Epidermic cells. ge. Gland cells of the epidermic 
layer. g. Nerve-ganglion cells. yp. Large clear cells, similar to those 
found in the eyes. 
that more careful searching, assisted by sections, may bring to 
light two more. Fig. 2 gives a section of one of the organs 
placed very near the margin on the ventral side, and Fig. 3 
represents a constructed section of one of the inner lateral 
sense-bulbs of the dorsal side. The organs of this row are not 
only larger, but more highly developed than those of the other 
rows. 
The relative prominence of a single row of these organs on 
each side, so well marked in the Clepsine I have examined, 
VOL. XXVI, PART 3.—NEW SER, DD 
