WOODWORTH; ILLINOIS TURBELLARIA. 9 
Smaller spots of deep brown or black occur scattered over the surface among 
the larger patches. In the largest, oldest specimens there are very few or none 
of the clear areas. Frequently a light median streak more or less free from 
pigment occurs, extending: backward from between the eye-spots (Fig. 3). 
Length 4 to 9 mm., greatest breadth 4 to 14 mm. 
Station D; 13,011, Station C; 18,113, Illinois R. at Havana; 22,050a, Sta- 
tion E ; 13,521, Station L; 22,020, Station K ; 22,033d, Station L ; 22,0110, 
Station L; 22,053, Station H. 
Planaria maculata is the commonest of our fresh-water Planarians and was 
the first one to be described (Leidy, 1848); however, nothing has been pub- 
lished regarding its sexual organs, and Iam unable to offer anything in this 
regard ; not one of the hundreds of specimens that came under my observation 
was sexually mature. The species, as already mentioned, is sluggish, seldom 
being in motion in the aquaria, and when stirred up in company with P. gono- 
cephala and P. dorotocephala it is the first to come to rest. It is possible, as 
also suggested by Leidy (1885, p. 50), that it is nocturnal in its habits. It is 
usually found on the protected sides of stones, of empty Unio shells, or of 
aquatic plants, and often huddled together in large numbers. 
About 40% of the Illinois individuals that I examined exhibited mutilations 
at the anterior or posterior ends, either by the absence of a head, or by being 
truncated posteriorly. In the cases where the posterior end is lacking the 
pharynx, instead of occupying a position midway between the anterior and 
posterior ends, extends almost to the posterior limits of the animal, There is 
no pigmentation about such scars. I have elsewhere (18968, p. 240) referred to 
the mutilations in Planaria maculata, and suggested that they were the result 
of reproduction by transverse division. I have since learned from Dr. Harriet 
Randolph that the species divides spontaneously, and that small fragments from 
any part of the body will regenerate into a new worm.! 
1 Through the courtesy of Dr. Randolph I am able to present the following 
table. The material upon which the experiments were made was collected on the 
island of Naushon, Vineyard Sound, Mass. 
PLANARIA MACULATA. CASES or FISSION. 
Specimen, Date of Isolation, lng ee Interval. poro i 
1 July 24 Rain July 80 
2 July 24 Rain August 1 
3 July 24 (?) Rain August 3 14 days | August 17 
4 August 17 * Laket | August 21 
5 August 17 (?) Laket | August 25 
6 August 18 Spring | August 20 
7 August 17 or 18 | Spring | August 2 
8 August 17 or 18 | Spring | August 28 
* 
Whole number isolated on August 17 and 18 was forty individuals, 
From which the Planarians came. 
= 
