170 



r. 1 REDA : 



Phascolosoma quadratum, n. Bp. 



Pl. VIII., figs. 1—4. 



The species in based on a single specimen found in the collection 

 (fig. 1). The worm is of a medium size ; the body-proper long and slender, 

 measuring 50 mm. in length and about 4 mm. in breadth. It ends post- 

 eriorly with a small conical swelling. The introvert, which is preserved 

 in the fully protruded state, is nearly as long as the body-proper, but much 

 narrower. The body is of a light brownish yellow color ; the surface, of a 

 rough appearance due to the presence of closely distributed skin-bodies 

 (fig. 2). These are relatively large (0.075 mm - in diameter), flat, 

 rectangular in form, and closely appressed. Each of the rectangular areas 

 is made up of very numerous chitinous granules closely set ; at the center 

 is seen a small clear space containing the external aperture of the subder- 

 mal gland. The skin-bodies are moderately uniform in size and shape 

 throughout the entire surface of the body-proper. However, in the hooked 

 region of the introvert, the)" are found as tubular papillae arranged 

 alternately with the hook-rows. Fig. 3<? represents the tubular papilla, 

 which is a colorless structure measuring 0.015 mnl - ' n height. Immediately 

 behind the tentacular region there follow about 30 ring-rows of hooks. 

 The latter (Fig. 3 b) are -very small, measuring 0.03 mm in height ; golden 

 yellow in color. Kach single tooth is sharply pointed and strongly curved. 



The longitudinal muscles are continuous. There are present only 

 two ventral rétracter muscles (vm, fig. 4). They arise near the posterior 

 extremity of the body. The dorsal vessel is as long as the oesophagus ; 

 without contractile villi. The intestinal convolution consists of about 30 

 spirals which are traversed through by the spindle muscle {s?n) fixed at the 

 posterior end of the body. No fixing muscle is present ; no rectal diver- 

 ticulum. The segmental organs (so) are about two-thirds as long as the 

 body-length, being fixed to the body-wall along their whole length. The 

 external openings of the organs are placed in the same level as the anus 

 (a). Two eye-spots are present on the ganglion. 



The present species seems to be closely allied to Pliascolosoma macer 



