GENERAL MORPHOLOGY OP THE GROUP. 
Ech. 3 
27. [Koehler, R.] Recherches sur l’appareil circulatoire des Oursins 
reguliers. C. R. xcv. pp. 459-461 [Ann. N. H. (5) x. pp. 408-410]. 
28. Ludwig, H. Entwickelungsgeschichte der A sterina gibbosci, Forbes. 
Z. wiss. Zool. xxxvii. pp. 1-98, pis. i.-viii. 
29. . Yerzeichuiss der von Prof. E. van Beneden an der Kiiste von 
Brasilien gesammelten Echinodermen. Mem. cour. Ac. Belg. xliv. 
4to, 26 pp. 
30. . List of the Holothurians in the Collection of the Leyden 
Museum. Notes Leyd. Mus. iv. pp. 127-137. 
31. Lyman, T. Reports on the Ophiuroidca dredged by H.M.S. ‘ Chal- 
lenger ’ during the years 1873-76. Challenger Reports, Zool. v. 
386 pp., pis. i.-xlviii. 
32. Marenzeller, E. v. Neue Holothurien von Japan und China. 
Yerh. z-b. Wien, xxxi. pp. 121-140, pis. iv. & v. 
33. Perrier, E., & Poirier, J. Sur l’appareil circulatoire des Etoiles 
de mer. C. R. xciv. pp. 658-661. 
34. . Sur l’appareil reproducteur des Etoiles de mer. Tom. cit. 
pp. 891 & 892. 
35. Perrier, E. Note sur les Brisinga. C. R. xcv. pp. 61-63 [Ann. N. H. 
(5) x. pp. 261-263]. 
36. . Sur une Asterie des grandes profondeurs de l’Atlantique, 
pourvuo d’un pddoncule dorsal. Tom. cit. pp. 1379-1381. 
37. Sladen, W. P. The Asteroidca of H.M.S. ‘Challenger’ Expe- 
dition (Preliminary Notices). I. Pier aster id<r,. J. L. S. xvi. pp. 
189-246. 
38. Tii^el, H. Report on the Holothuroidea dredged by H.M.S. ‘ Chal- 
lenger* during the years 1873-76. Part i. Challenger Reports, 
Zool. iv. 176 pp., pis. i.-xlvi. 
On the colouring matters of Echinoderms consult C. F. W. Kruken- 
berg’s “ Yergleichend Physiologische Studien” (Heidelberg: 1882), 
Ser. 2, Abth. i. p. 148 (Albinism in Cucumaria planci ), p. 179 ( Holothuria 
poll , &c.); on asterocyanin, see Abth. iii. p. 70, and on the colouring matter 
of Antedon rosaceus , p. 88. 
“ Die Schutzdecken der Echinodermen,’* op. cit. Abth. i. pp. 35-48. 
On the Perivisceral Fluid of the Sea-Urchin and its coagulation, see 
E. A. Sciiafer, P. R. S. xxxiv. pp. 370 & 371. 
For a good popular account of the Echinodermata , see P. H. Car- 
penter in Cassell’s Natural History, vol. vi. (1883, published in 1882), 
pp. 259-276. 
General Morphology of the Group. 
Carpeuter (11) continues his discussions of the morphological results of 
various inquirers, and expresses doubts as to whether, after all, the central 
