238 CLASS vii. 



Sp. Chcetopterus pergamentaceus Cuv., MILNE EDWARDS Ann. desSc.nat. Tom. 

 xxx. PL 11, fig. i, Cuv. R. Ani. ed. ill., Anntt. PI. 10, fig. i ; in the West 

 Indian Sea. A species of this genus occurs also in the Mediterranean. 



Family IX. Peripatina. The rudiments of feet are conical 

 tubercles, supplied with a fasciculus of thinly set setae at the point. 

 Head distinct, provided with two cirri (antennae) annulate, large, a 

 short proboscis, and two jaws. 



Peripatus LANSDOWN GUILDING. Body with few segments 

 subdivided by annulate folds, obtuse at both extremities, gibbous 

 above, plane beneath. 



Sp. Peripatus iuliformis LANSDOWN GUILDING, Zool. Journal, n. PI. xiv. 

 fig. i ; AUDOUIN and MILNE EDW. Ann. des Sc. nat. Tom. xxx. pp. 412 

 414, PI. 11, figs. 5 7 ; West Indies. This animal would seem, according 

 to some, to be a myriapod insect ; the English author who first made it 

 known, considered it to be a mollusc. MILNE EDWARDS, on anatomical 

 grounds, defends its reception into this class ; Ann. des Sc. nat. sec. SeY. 

 XVIII. Zoolog. pp. 126 128. Branchice are not present, if the conical 

 rudiments of feet are not to be considered as respiratory organs. 



Family X. Aricice. Body cylindrical, attenuated at both ex- 

 tremities, with head little distinct. Proboscis short, without jaws. 

 Kudiments of feet with cirrus usually single; branchiae either none 

 distinct or resembling cirri or lobes adhering to the 'base of the feet. 



This small group, regarded by AUDOUIN and MILNE EDWARDS as 

 a distinct family, contains imperfect ringed worms, which in part 

 belong to the Nereids of former writers. Where no special gills are 

 present, the cirri appear to serve for respiration. 



Cirratulus LAM. Body elongate, round, with few dorsal and 

 ventral setae remote, and long dorsal cirri. The branchiae very long 

 cirri in the anterior part of the body. 



Sp. Cirratulus borealis, Lwribricus cirratus MUELL., 0. FABEICII Fauna 

 grcenl. pp. 281 283, fig. 5, Encyclop. meth., Vers. PI. 34, figs. 10 12 ; 

 Cirrat. Lamarckii AUD. and EDW. Ann. des Sc. nat. xxvii. PI. xv. figs. 

 i 4, xxix. pp. 410, 411 ; GRUBE Kiemenwurmer, 1838, pp. 32, 33. 



Ammotrypana B-ATHKE (Beitr. z. Fauna Norweg.) A genus 

 related to the preceding: it differs by defect of the long cirri (bran- 

 chiae) in the anterior part of the body. 



Sp. Ammotrypana aulogaster BATHKE, 1. 1. p. 188, Tab. x. figs, i 3, &c. 



Ophelia SAV. Comp. EDW. and AUD. Ann. des Sc. nat. xxix. 

 pp. 403 407. According to SAES the animal is so described that 



