I. Morphological and Physiological Works of a General Character. 3 



Pouchet, G., & ... Chabry, 2. De la production des larves monstrueuses d'Oursin par priva- 



tion de chaux. in: Compt. Rend. Tome 108 p 190198. [17] 

 Ringueberg, E. N. S., The Calceocrinidae. A Revision of the Family, with Descriptions of 



some new Species, in: Ann. New York Acad. Sc. Vol. 4 p 388408 T 10, 11. [12j 

 Sarasin, P. & K, Uber die Anatomic der Echinothuriden und die Phylogenie der Echino- 



derrnen. in: N. Jahrb. Miu. Geol. Pal. 2. Bd. p 5459. [18] 

 Semon, R., 1. Die Homologien innerhalb des Echinodermenstammes. in: Morph. Jahrb. 



15. Bd. p 253307. [5] 



, 2. Ein Fall von Neubildung der Scheibe in der Mitte eines abgebrochenen Seestern- 



armes. in: Jena. Zeit. Naturw. 23. Bd. p 5S5 594 T 29. [16] 



Sladen, W. P., Report upon the Asteroidea collected by H. M. S. "Challenger during the 

 years 187370. in: Rep. Challenger Vol.30 Part 51 42 and 893pgg.Fig. 117 Taf. [12 j 



, v. Duncan. 



Sluiter, C. Ph., Die Evertebraten aus der Sammlung des Konigliehen Naturwissenschaft- 

 lichen Vereins in Niederliindisch Indien in Batavia. Die Echinodermen. II. Echi- 

 noidea. in : Nat. Tijd. Nederl. Indie Batavia 48. Deel p 285313. [8] 



Springer, F., v. Wachsmuth. 



Topsent, E., Differenciation remarquable d'un tube genital male de Cucumaria pentactes L. 

 in: Bull. Soc. Linn. Normandie (4) Vol. 2 p 112114. [23] 



Wachsmuth, C., & F. Springer, 1. Discovery of the Ventral Structure of Taxocrinus and 

 Haplocrinus, and consequent modifications in the Classification of the Crinoidea. in : 

 Proc. Acad. N. Sc. Philadelphia p 337363 T 18. [11] 



, 2. Crotulocrinus \ its Structure and Zoological Position, ibid, p 304 390 T 19,20. 



I. Morphological and Physiological Works of a General Character. 



Korschelt ( ! ) discusses Selenka's theory of the bilateral origin of the meseii- 

 chym in Echinoderms with Metschnikoff's refutation of it, and points out that 

 the recent observations of Barrels and Bury do not support its extension to the 

 Crinoids. His own investigations on the blastula of Strongylocentrotus Hindus show 

 that the supposed primitive niesenchym cells are merely incompletely developed 

 stages of the ordinary blastula cells. These increase more quickly at the thickened 

 vegetative pole than elsewhere, so. that the wall of the blastula becomes irregular 

 and more than one cell deep. Its inner cells are gradually pushed into the blasto- 

 coel and become wander cells, but there is no regularity about their formation. 

 In fact, short cells may be found intercalated among the high prismatic ones over 

 the whole blastula, but they eventually develope into the latter form. The for- 

 mation of wander cells follows no definite rule, and they group themselves quite 

 irregularly in the blastocoel, without any indications of forming two niesenchym 

 bands. The mesenchym of Ophiurids and of Cucumaria is formed in the same 

 manner ; while in other Holothurians it does not appear till the commencement 

 [Holothuna] or near the completion of gastrulation. In the latter case it arises 

 from the blind end of the archenteron as in Asterids and Crinoids. This appears 

 to be the more primitive condition, as the rest of the inesoderm arises there with 

 the vaso-peritoneal sacs. Consolidation of the latter in the Urchins, Ophiurids, 

 and Cucumaria throws the mesenchym formation back to the blastula stage. The 

 primitive Echinoderm condition seems to present itself in the Nemertines, the 

 rnesenchymatous and enterocoelian structures having a common origin. A higher 

 phylogenetic stage is the development of enterocoel sacs, which occurs in the 

 Echinoderms, together with the more primitive mesenchym formation. The fact 

 that the latter appears in Synapta, while the modified development occurs in 



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