PLANARIA. : 101 
PLaTE XV. 
Fic. 1. Supposed larvee of the.Planaria cornuta from the spawn. 
2. Larvee farther advanced. 
3. Empty capsules. 
Note-—The preceding is the only species of Planaria known to me 
with large and distinct horns towards the front of the head. But a num; 
ber of years ago another occurred, to which I shall be content with a 
general allusion, having been unable to resume my littoral researches 
when most likely to be successful, and that also was horned. 
Length about eight lines ; extreme breadth three ; body thin, flat- 
tened, dingy yellow, and, on the whole, much resembling the Planaria 
flewilis, both in aspect and motions. ‘Two very short obtuse white horns, 
projecting not the fourth of a line, rose perpendicularly from the upper 
surface, in nearly the same position occupied by the ocular specks 
of the flevilis; and on the interior of the root of each horn, were 
eight or ten minute specks, disposed irregularly. Spawn, consisting of 
spherical ova or capsules, was deposited in September. When farther 
advanced, each capsule seemed to consist of four compartments. 
Whether this was a specimen disfigured by some monstrosity, or 
whether the organs were natural, I cannot presume to determine. The 
artist had no hesitation regarding its form. 
Pate XIV. 
Fic. 5. Planaria (corniculata), back. 
6. Belly. 
7. Spawn. 
8. Portion of the same, enlarged. 
_6,—PLANARIA ELLIPSIS.—Plate XIV. Figs. 9, 10, 11, 12, 13, 14, 15, 16. 
As many of the lower animals gain an important accession of parts 
with age, I mistook this species for a long time as the young of the Pla- 
naria cornuta. Further experience proved their difference. 
Length four or five lines, or somewhat more ; breadth half an inch ; 
