ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 177 



is simple cell multiplication ; then there appear large sub-epithelial 

 dermatoblasts ; finally these break up into ordinary reparative cells. 



The new nerve-cord is wholly ectodermic, and the old cord does not 

 help in its making. The metamerism of the repaired portion is at first 

 entirely internal. 



In the reparatory proliferations there is mitosis throughout, though 

 there are a few direct divisions at the outset. 



In general terms, it may be said that the regenerative process is 

 much more plastic and less stereotyped than the normal ontogeny ; 

 but regeneration, like every other process, is under the sway of heredity 

 and adaptation. 



- We have not been able to do more than select a few of the general 

 conclusions of this interesting investigation. 



Bythonomus lemani G-rube.* — Ernile Piguet has a brief note on 

 the occurrence of this Oligochaete in Lake Geneva, and on the history 

 of its discovery by Claparede and by G-rube. He shows that B. lemani 

 Grube is equivalent to Glaparedeilla integrisetosa (= 0. meridionalis) 

 Vejdowsky. 



Nematohelminthes. 



Death from Infection with Ascaris. f — H. Ziemann reports a case 

 of a negro boy in Kameroon who died with symptoms of peritonitis. 

 The post-mortem examination showed an extraordinary abundance of 

 Ascaris lumbricoides in the intestine. Four litre glasses were filled with 

 them. Two were free in the peritoneal cavity, and there were two 

 round holes in the wall of the intestine. 



J Rachis Nucleus in Ascaris. | — Harry Marcus finds — what has 

 escaped previous observers — that there is a very distinct nucleus in the 

 rachis of Ascaris megalocephala. It is probable that the rachis should 

 be regarded as a giant cell, possibly with more than one nucleus. In 

 one ovarian tube of A. megalocephala two rachis-nuclei occurred. In 

 A. mystax one rachis-nucleus was found. 



Platyhelminthes . 



Turbellaria Acoela. § — L. von Graff has prepared the systematic 

 account of the Turbellaria Acoela for " Das Tierreich." He deals with 

 7 genera and 32 secure species. All are marine, littoral or pelagic. One 

 form, Haplodiscus incola (Leiper), lives as a parasite in Echinocardium 

 cor datum. There are the usual diagnostic tables and keys. 



Origin of Species in Cestodes.|| — Guido Schneider discusses the 

 question of the origin of species in the case of Cestodes, especially 

 Ichthyotamiae, and gives evidence of the divergence in the external 



* Rev. Suisse Zool., xiii. (1905) pp. 617-19. 



t Arch. Schiffs- una Tropen-Hygiene, ix. (1905) pp. 33-4. See also Zool. Zen- 

 tralbl., xii. (1905) p. 634. 



\ Biol. Centralbl, xxv. (1905) pp. 479-82 (3 figs.). 

 § Das Tierreich, 23 (1905) 35 pp. (8 figs.). 

 || Biol. Centralbl., xxv. (1905) pp. 349-52. 



April 18th, 1906 n 



