102 XV. Echinodermata (init Einschluss der fossilen) für 1899. 



und, falls das Tier dadurch wieder zum Leben erwachte, nochmals er- 

 wärmt; dies wurde so oft wiederholt, bis das Tier wirklich getötet war. 

 Bei Echinus microtuberculatus : Paralyse trat bei 37,2 — 37,8°, Tod 

 bezw. bei 39,1 und 38,8 ^ ein, bei Strongylocentrotus lividus bezw. 

 40,2° und 40,7°. 4 Stunden alte Blastulae von Strongylocentrotus 

 wurden durch 33,5°, 28 Stunden alte Plutei durch 39,5°, 6 Tage 

 alte durch 40,3° Wärme getötet. Als Resultat: ,,the deatli tempe- 

 rature rapidly rises with progress in the development of the im- 

 pregnated ovum, so as ultimately to be increased by nearly 12 °". 

 Aber wir sind ,,as much as ever in the dark as to why the tissues 

 of various animals, or the tissues of the same animal in different 

 stages of development, are affected dilferently by exposure to high 

 temperature." 



— (3). The Effect of Staleness of the Sexual Cells on the Deve- 

 lopment of Echinoids. With 1 diagr. In: Proc. R. Soc. London, Vol. 65, 

 No. 420. p. 350—60. — Ausz. in: Journ. R. Micr. Soc. London 1900. 

 P. I, p. 65. 



Verf. gibt selbst flg. Resümee: ,,(1) If the ova and sperm of the 

 Echinoid Strongylocentrotus lividus be kept for various times in sea 

 water before fertilisation, then for about the first twenty to twenty- 

 seven hours the number of normal blastulae formed diminishes only 

 about 1 per cent per hour. After this abnormal development sets 

 in rapidly, so that generally after a further nine hours or so, no blastulae 

 at all are obtained. The rate of falling off in the number of normal 

 blastulae may increase to as much as 18. 9 per cent per hour. 



(2) If ova not more than twentyseven hours stale be fertilised with 

 equally stale sperm, practically as many blastulae are obtained as 

 when stale ova are fertilised by fresh sperm or fresh ova by stale sperm. 

 After twentyseven hours, howewer, the number of blastulae obtained 

 with both products stale falls off more rapidly. 



(3) Larvae obtained from stale ova and stale sperm are of practi- 

 cally the same size as those from fresh sexual products, but those 

 fresh ova and stale sperm are distinctly larger than the normal, whilst 

 those from stale ova and fresh sperm are distinctly smaller." 



Verrill, A. E. (I). Report on the Ophiuroidea coli, by the Baliama 

 Expedition from the University of Jowa in 1896. With 8pls. In: Bull. 

 Laborat. Nat. Hist. State of Jowa. Vol. 5. No. 1. (87 pp.) — Ausz, 

 von H. Ludwig in: Zool. Centralbl. 7. Jhg. No. 12—3. p. 4.34. 



Etwa 66 Arten gesammelt; wahrscheinlich fehlen viele in der Tat 

 häufige Arten. — Fam. Pectinuridae «. noin. (= Ophiodermatidae). 

 6 Ophiura- Arten ; neu: O.fallida n. sp. (mit 0. rubicunda verwandt). 

 1 Pectinura. 1 Ophiopeza. 1 Ophiopaepale. — Fam. Ophiolepidae. 2 Ophi- 

 ozona; neu: O.nivea Lym. v. compta ii. var. (,,with separated radial 

 shields"), auch die f.pr. beschrieben. 1 Ophiothyreus. 1 Ophioglypha. 4 

 Ophiomusium ; neu : 0. eburneum Lym. v. elegans ii.var., 0. stellahmi u.sp., 

 0. sculftum n. sp. 1 Ophioconis (miliaria Lym.; beschrieben!). — 

 Fam. Ophiothrichidae ; beschrieben. 3 Ophiothrix (angulata [Say], 

 oerstedi Lütk., suensoni Lütk., alle beschrieben). — Fam. Ophio- 



