186 UNITED STATES NATIONAL MUSEUM BULLETIN 251 



several lobes, or divided into about 20 lobules. Two to four elongate 

 gonads on both right and left sides; some branched (fig. TSc). Tes- 

 ticular follicles very numerous, arranged roughly in two rows on 

 attacliment surface of gonad; follicles somewhat irregular in shape 

 when fully matured, and may extend to and cover lateral side of gonad. 

 Remarks. — The internal structure of these two specimens very 

 closely resembles that of Cnemidocarpa macrogastra known from 

 Japanese waters. However, the relative size of the stomach is some- 

 what smaller in the present specimens than in C. macrogastra. More- 

 over, the distance between the apertures is much larger in the former 

 than in the latter. 



95. Cnemidocarpa incuhita (Sluiler) 



Figures 79, 80 



Styela incuhita Sluiter, 1904, p. 75, pi. 2, fig. 7; pi. 9, figs. 11-14. 



MATERIAL EXAMINED 



Mabianas Islands : Saipan Island ; lagoon, Tanapag Harbor. P. E. Cloud, sta. 

 D-7. One specimen ( USNM 11500) . 



Description. — A 9 mm. specimen from Saipan Island was exam- 

 ined. Animal densely encrusted with white coarse sand grains except 

 ventral side, by which it attaches to substratum, test very thin here. 

 Branchial aperture subterminal, atrial aperture well apart from 

 branchial; both apertures sessile, 4-lobed. Test translucent, tough, 

 milky white. Mantle extremely thin, adheres firmly to test. On 

 mantle body anterior margin of atrial aperture situated at middle of 

 body. Very fine tentacles along atrial velum. Endocarps present on 

 inner surface of mantle. 



In branchial sac inner longitudinal vessels arranged (D= dorsal, 

 V= ventral) : 



Left D 1 (11) 1 (7) 1 (9) 2 (7) 1 V 



Right D (10) 1 (9) 1 (9) 1 (8) 1 V 



Transverse vessels nearly of same thickness, parastigmatic vessels 

 found at some parts of sac. Stigmata 5 to 7 elongated in each mesh, 

 may be up to 9 in those along endostyle. Tentacles about 25, larger and 

 smaller ones differentiated. Ciliated groove a longitudinal slit, margin 

 dotted with pigment spots. First intestinal loop very elongated, an- 

 terior end reaches slightly beyond middle of body. Axis of second 

 intestinal loop passes through cardiac end of stomach, which is elon- 

 gated and occupies approximately one-half of ventral branch of first 

 intestinal loop. Plications on stomach surface 17; a remarkably large 

 caecum found at inner pyloric corner, tip strongly curved towards 

 ventral side, whole caecmn connected to various parts of intestinal loop 

 by several haemal vessels (fig. 79c?). Esophagus very short. Anal 

 margin thickened, forming 8 distinct lobules. On left 8 elliptical 

 "•onads and 10 on right side. Testis occupies attachment surface of 



