372 



PROF. r. J. BELL, ON HOLOTHXJRIA NIGRA. [May 20, 



EXPLANATION OF THE PLATES. 



Fig. 1. Cioniscus gracilis, p. 34L 



2. siriafus, p, 342. 



3. Odosfo7nia sicbMovffci 



4. — ffinoi.ix. n. S47. 



striatum, ^, 



fomia svb6b!o7iffa, p. 345, 

 tenuis, p. 347. 



5. — ^— iiiteiis, p. 349. 



Plate XXVI. 



Fig. 6. Odosfomia fralonga, p. 350. 



7. crassa, p. 350. 



8. wnifcifciata, p. 351. 



9. sigmoidea, p. 354, 



10. flexuosa. p. 355. 



Plate XXVII. 



Fig. 1. Odosfomia sinuosa, p. 358. 



- acuticostata, p. 359. 

 -fulgidula, p. 359. 



- attcnuata, p. 360. 



- comprcssa., p. 3fi0. 



- paucistriata, p. 361. 



2. 

 3. 

 4. 

 6. 

 6. 



Fig. 7. Odosfomia semicosfafa, p. 361. 



8. Pi/mmidella nitidula, p. 363. 



9. Mafhikiaquadricarinata (apex), 



p. 364. 

 10. Gegania pinguis, p. 365. 



Plate XXVIII 



Fig. 1. Etdima jeffreysiana, p. 366. 



2. glabra, p. 367. 



3. stalioi, p. 368. 



4. solida, p. 368. 



5. fusco-apicata, p. 369. 



Fig. 6. Eulima piriformis, p. 369. 



7. ahhreviafa, jj. 370. 



8. — — ■ swhumbilicata, p. 370. 



9. minxta, p. 370. 



10. obtma, p. 370. 



3. Studies in tlie Holothuroidea. — IV. On the Structural 

 Characters of the Cotton- Spinner {Holothvria nigra), 

 and especially of its Cuvierian Organs. By F. Jeffrey 

 Bell, M.A., F.Z.S.^ Professor of Comparative Anatomy 

 in King's College. 



[Eeceived May 15, 1884.] 



Scattered through zoological literature there are here and there 

 refereuces to a Holothuriaii, of which Selenka appears to have had 

 no knowledge, and whicii Semper ])laces among the "giinzlich 

 zweif'elhaftcn Arten," but which, unless patriotism is a fault in a 

 man of science, ought to be of interest to British naturalists in so 

 far and inasmuch as it is not only the only known British repre- 

 sentative of the restricted genus Holothuria, but it is, so far as we 

 know at present, the only member of the family of Aspidochirota), 

 or Holothurians with shield-shaped tentacles and no retractors for 

 the i)harynx, that is found in ovir seas. Discovered shortly after the 

 publication of Forbes's ' British Starfishes ' — which, like every other 

 work from that accomplished pen, had a remarkable influence on 

 liis contemporaries — it was first mentioned and described to a scien- 

 tific audience by Mr. C. W. Peach in 1844, who appears (see 

 Report, 1844, p. 6.5) to have satisfied the members of the British 

 Association that, in introducing to them the '* nigger or cotton- 

 spinner," he was speaking of a Ilolothurian new to the British 

 fauna. A communication on this animal was read by Mr. Peach to 

 the Royal Polytechnic Institution of Cornwall, and is to be found, 

 with an illustrative plate, on pp. 1 /l-l 74 of the 'Annals and Magazine 



