PLANARIA. 121 
of the same year, taken from the marsh, September 22. Few ‘were 
large. Fertile specimens contained four, five, or six brown ova, seldom 
more, dispersed through the body, and many had none. Where only a 
single ovum appeared, it was on the right or left side of the body indif- 
ferently. None of the Planariz survived above a month, nor were any 
of the ova productive of young. Thus I was disappointed again. 
This Planaria inhabits few districts. 
g-—Ptanaria cunEuUs—The Wedge Planaria.—Plate XV. Figs. 15, 16. 
This is a minute fresh-water Planaria, somewhat representing the 
side of a wedge, inhabiting Blackhall Pond. Length not exceeding a 
third of a line. Head obtuse, the corners rounded as it advances, and 
the portion between them depressed. Body thick, flattened ; tail acute. 
Colour greyish-brown No eyes visible. Taken in August. 
Priatse XV. 
Fig. 15. Planaria cuneus, enlarged. 
16. The same, magnified. 
17. The same, more highly magnified, 
h.—PLANARIA PRASINA—Grass-Green Planaria.—Plate XV. Fig. 21. 
Length of the largest about half a line ; thickness about the fifth of 
the length. Body roundish ; head obtuse ; tail tapering to a point. Co- 
lour beautifully grass-green. Motion active. Several congregate on the 
side of the vessel containing them. If in a watch-glass they be subjected 
to the microscope, they will be observed to pass at the edge of the water 
on the side next the light. One or two brown ova seemed to be in one 
or two specimens. No eyes visible. 
Drawn up with the roots of the Water Plantain in Blackhall Pond, 
in August. 
Great disparity of size observable among a group. 
PLATE XV. 
Fic. 21. Planaria prasina. 
