298 bulletin: museum of compakative zoology. 



(not T. mttatum VerrilP ), and 7'. quadristriatimi Langerlians^ in 

 general appearance, and in having four longitudinal brown lines on 

 dorsal surface. In the former species, however, the four lines usu- 

 ally become confluent behind the head in two quadrangular patches 

 which send two fine lines between the posterior pair of ocelli ; in 

 the latter species the two median lines extend to the tip of the head 

 before uniting, while the lateral are interrupted between the ocelli 

 and do not unite on tip of head. In T. quadrilineatum^ as described 

 below, the median lines reach nearly to tip of snout, bvit do not join 

 each other, while the lateral lines usually end behind the ocelli. 



Body short, broad and stout ; somewhat flattened but with 

 rounded margins ; head usually narrower than, body ; provided with 

 the usual pair of lateral oblique grooves which appear as slight con- 

 stiictions opposite the posterior pair of ocelli. Intestinal caeca not 

 much branched ; reaching to brain region. 



Size. — Length when sexually mature 8-12 mm.; width less than 

 1 mm. 



Color. — General color of body whitish, with four longitudinal, 

 deep brown stripes, two of which lie near lateral margins of body, 

 the other two being placed symmetrically on the dorsal surface (PI. 

 2, fig. 18). Dorsal stripes about equal in width to the white median 

 stripe which lies between them. They are narrower on head, and 

 terminate anteriorly a little in front of the anterior pair of ocelli. 

 Lateral stripes strictly marginal, much narrower than dorsal, and 

 usually present a ragged appearance. They each terminate anteri- 

 orly in the vicinity of the lateral grooves on the head or a little 

 behind them. 



Head and esophageal region usually pure white except for the 

 brown stripes ; occasionally pale yellowish or flesh color. Intestinal 

 region with tinge of yellow or salmon, due to color of intestinal 

 lobes which show through other tissues. Ventral surface of same 

 color as dorsal, but often with a tinge of salmon, flesh color, or 

 greenish yellow in intestinal region. Proboscis whitish ; brain pale 

 yellow. Brown stripes of body remain conspicuous after preserva- 

 tion. 



Ocelli of medium size, arranged nearly in the form of a square 



1 Amer. Journ. Sci., 7, p. 45, 1874. 



2 Zeits. f. wiss. Zool., 34, p. 136, 1880. 



