OF THE EI7CHLANID0TA. 



699 



tion ; all have peculiar vesicles at the back, 

 fiireate. 



They resemble Monura. Foot 



CoLUEUS (?) iincinatus (Brachionus 

 xuicinatus, M.). — Lorica ovate, com- 

 pressed ; posterior and bi-pointed toes, 

 very short ; at the middle of the back is 

 generally a circlet of vesicles, which at 

 one time Ehrenberg considered eyes, but 

 which he now regards as vesicles of oil, 

 as they are seen in all the species, and 

 abmidantlv in the Cvclopida. In fresh 

 and sea water. 1-436" to 1-288". 



C. (?) hicmpidatus. — Lorica ovate, 

 compressed ; the two points posterior, 

 sti'ong J toes short. 1-288". 



j C. caudatus. — Lorica ovate, com- 

 pressed, posterior points distinct ; toes 

 ! longer than the foot. The shell re- 

 I sembles C. imcinatus, but the toes are 

 i much longer. In fresh and sea water. 

 1 Lorica 1-288". 



I C. deflexus. — Lorica ovate, compressed ; 

 j the shell is more rounded, and very 

 I transparent, (xxxiv. 460-462 represent 

 ; back, under, and side views ; the former 

 shows the vesicles.) In the clear water 

 of a peaty moor. 1-240". 



Genus METOPIDIA (XXXIV. 463-465).— Eyes two, frontal ; foot fur- 

 cate ; lorica depressed or prismatic ; the frontal portion naked or uncinate, 

 not provided with a hood ; indeed they may be regarded as Lepadelhe with 

 two red frontal eyes ; the lorica, which is oval and semiciix-ular or crescentic 

 in front, appears to be closed on the under side (testuJa). In two species the 

 rotary organ has from three to four muscles ; and in one species two foot 

 muscles are observed. Two species have a fi'ontal hook, like Colurus. The 

 oesophageal bulb in one species has two, in another four, but in the third no 

 distinct teeth ; a short oesophagus and two spherical glands are present in 

 all. Two species have a distinct constricted stomach (Gasterodela). An ovary 

 is present ; and M. triptera has a contractile vesicle. Eye, according to Leydig, 

 with a lens. 



Metopidia LepadeUa. — Lorica de- 

 pressed, nearly flat, broadly ovate, ex- 

 cised in a lunate manner in front, 

 roimded posteriorly ; toes somewhat 

 longer than foot. This species resembles 

 in foi*m LepadeUa oralis (xxxiv. 430- 

 433) and Squamella Bractea \ but the 

 foniier has two-toothed jaws and no 

 eyes ; the latter, four eyes and indi- 

 stinctly-toothed jaws, (xxxiv. 463-465, 

 back, under, and side \news, the first 

 and last having the rotary organs ex- 

 tended and in motion.) 1-240". 



M. acuminata. — Lorica depressed, 

 nearly flat, oval in shape ; anteriorly 

 slightly excised, posteriorly pointed. 

 This species resembles Colurus j but in 

 that genus the eyes are very close to- 

 gether, and the lorica open beneath. 



Amongst Oscillatorise. 1-240". 



M. triptera. — Lorica oval, triangular, 

 back crested : a section would resemble 

 XXXIV. 443. Amongst Confeiwse. 1-200". 



M. solida (Gosse). — Much resembles 

 31. LepadeUa, but is considerably larger ; 

 lorica circular, brilliantly transparent ; a 

 slight pimctation siurounds the edge, 

 like that on a coin. Lorica 1-150". 



M. oxysterna. — Resembles M. triptera, 

 but the dorsal keel is much higher and 

 thinner; the anterior two-thirds of the 

 ventral sm-face form a prominent ridge, 

 terminating abruptly like the breast- 

 bone of a bird ; and the posterior portion 

 is hollowed out remarkably. Viewed 

 laterally, the outline of the back is very 

 gibbous behind. Lorica 1-175". 



Genus STEPHAXOPS (XXXIV. 466, 467; XL. 8-10).— Eyes two, 

 frontal ; foot fiu'cate ; lorica depressed or prismatic, the front expanding 

 into a hood or transparent shield. The lorica, in two species, has thorn-like 

 processes posteriorly. In one species a longitudinal muscle is observed on 

 each side (anteriorly), two muscles for moving the foot, and from three to five 

 belonging to the compound rotary organ. The oesophageal bulb has single- 

 toothed jaws, and a short oesophagus. In one species the alimentary canal 

 is constricted, in the others it is simple ; two species have glands ; an ovary 



