CYCLOBRACHIA AURICULATA 



369 



45/x across, and the tips of the bow are a little less than 40/x apart. The broad 

 dorsal ciliated band begins at the front edge of the metasoma (Fig. 1455). In 

 the hind part of the preannular region of the trunk are scattered papillae 

 also furnished with plaques. The well-developed girdles are both interrupted 

 dorsally and ventrally. The ventral ends are wide apart and point backwards, 

 while the dorsal ends almost meet (Fig. 145£, F). A few round mid-ventral 

 papillae lie in the neighbourhood of the girdles, 

 with a prominent larger one behind the second 

 girdle. The toothed platelets, 15-26/x long and 

 5-8/u. across, are arranged in 3-5 rows (Fig. 

 145G). The front end of each is a little narrower, 

 and the whole surface is covered with teeth which 

 point forwards; the anterior group of teeth is 

 thus absent (Fig. 145//). The postannular 

 section of the metasoma begins with a nipped-in 

 waist, on which lies the large ventral papilla men- 

 tioned above. Each of the well-marked, meta- 

 meric, transverse rows of papillae consists, as a 

 rule, of five small, rounded papillae bearing trans- 

 verse, cuticular plaques which are slightly bent 

 with the ends slanting backwards (Fig. 1457). 



The fore-part of the body is 2 mm long; the 

 front part of the mesosoma is 0-55 mm broad, 

 and the back part 0-43 mm; the metameric part 

 of the preannular region is 38 mm long, the 

 total preannular region 58 mm, and the post- 

 annular 57 mm. The metameric part is thus two- 

 thirds of the total preannular region, and the 

 overall length of the body, excluding the ten- 

 tacles, is 117 mm. 



Fig. 146. Cyclobrachia auriculata : 

 spermatophore. 



Fig. 145. Cyclobrachia auriculata : A - front end of the body of a male from the ventral, В - from 

 the dorsal, and, С - from the left side ; D - cuticular plaques from the metameric papillae of the 

 preannular region of the metasoma; E - region of the girdles in dorsal, and, F - in ventral view; 

 G - part of a girdle; H - toothed platelet; I- part of the postannular region. 

 an - girdles; au - dorsal ear-shaped lobes; с - cephalic lobe; со - dorsal ciliated band;/- keel of 

 the bridle; go - genital papilla; gp - genital aperture; ms - mesosoma; mts - metasoma; p - cuti- 

 cular plaques; pa - papillae; pa 1 - ventral papilla lying behind the girdles; pa 2 - transverse rows of 

 papillae of the postannular region ; ps - protosoma ; s 1 - groove between the protosoma and the 

 mesosoma ; s 2 - groove between the mesosoma and the metasoma ; s* - post-tentacular groove ; 

 sv - ventral sulcus ; tc - crown of tentacles. 



