WOODWORTH: TURBELLARIA. 241 
*Procotyla fluviatilis Leipr.! 
Procotyla fluviatilis LEIDY， The Museum, Vol. I. p. 50, Philad., 1885. Stimpson, 
Proc. Acad. Nat. Sci. Philad., Vol. IX. p. 23, 1857. DIESING，Sitzungsb， 
Akad. Wiss. Wien, Bd. XLIV. Abth. 1, p. 517, 1862. GirarD, Ann. Sci. 
Nat., Zool., Tom. XV. p. 164, 1893; Nord Amerik. Monatsbericht f. Naturw. 
u. Heilk., Philadelphia, Bd. II. p. 2, 1851. Woopworrn, Bull. Mich. Fish 
Commission, No. 8. 1896. 
Dendroewlum superbum GIRARD, Proc. Bost. Soc. Nat. Hist., Vol. III. p. 265, 1851. 
Lerpy, Proc. Acad. Nat. Sci. Philad., Vol. V. p. 288, 1852. 
“Round Lake, July 9, 1894. Catalogued as “ white planarian.” Without 
doubt this is the Pl. fluviatilis of Leidy. 
RHABDOCQLIDJZE. 
Mesostoma Wardii Wowrn. 
Figure 2. 
Mesostoma Wardii WoopwoRTH Bull. Mich. Fish Commission, No. 8. 1896. 
Nine specimens from “alge Aug. 20, 1893, New Baltimore,” Lake St. Clair. 
Length 2-3 mm., greatest breadth 1-1.4 mm. Very thin and flat. Anterior 
end tapering, conical, rounded, marked off from the body by a slight constric- 
tion. Posterior end tapering sharply, and terminating in an acute caudal 
process, Pharynx large, prominent, in front part of middle third of the body. 
No distinct tracts of rhabditi (“ Stäbchenstrassen ”) at anterior end. Nothing 
definite could be determined in regard to the sexual organs. Most of the 
specimens immature ; the one figured, more nearly mature than the others, 
contains nine ova in each side of the uterus. Color of alcoholic specimens 
yellowish, very translucent. 
Mesostoma viridatum M. Scu. 
Mesostoma viridatum Max Scuuutze, Beiträge zur Naturg. d. Turbell., pp. 16-19, 
1851. Woopworru, Bull. Mich. Fish Commission, No. 8. 1896. 
Seven specimens from * Utricularia washings, West Twin Lakes, Charlevoix, 
Aug. 13, 1894.” A note on the label reads, “Small forms green.” M. viri- 
datum is acosmopolitan species, occurring in all continental countries of Europe, 
and in Scotland, Greenland, and New Zealand. This is the first record of its 
capture in the United States. 
1 The species marked with an asterisk were not sent to me. The accounts here 
given are from notes and drawings by Prof. H. B. Ward. The quotation marks 
refer to the labels or Prof. Ward's notes. 
