191 



bildet jede derselben einen seitlichen Zellenstrang. Dieser zerfällt 

 der Länge nach in drei rundliehe Zelleuhaufen , welche in ihrem 

 Innern Borsten erzeugen , zugleich aber auch eine dünne Zellen- 

 schicht dorsal wärts entsenden. — Die Anlage des Centraine rven- 

 sy Stern s besteht in einer «Scheitelplatte« (Hirn) und einer ventralen 

 Ectodermverdickung (Bauchmark), welche unabhängig von einander 

 erscheinen; die Augen der Larve entstehen im Ectoderm, so wie 

 auch die ersten Tentakeln rein ectodermale Bildungen sind. 



Von der Entwickelung der Spirorbis nautüoides sei hier nur er- 

 wähnt, dass dort eine vollkommene bilateral-symmetrische Gastrula 

 besteht, und der Mund an der Stelle sich bildet, wo das Prostoma lag. 

 Das Mesoderm scheint den gleichen Ursprung zu haben wie bei Nereis. 



III. Mittlieilungen aus Instituten, Gesellschaften etc. 



1. Zoological Society of London. 



15th March, 1881. — The Secretary read a report on the additions 

 that had been made to the Society's Menagerie during the month of February, 

 and called special attention to a female Bactrian Camel [Camelus bactrianus) , 

 formerly belonging to Ayoub Khan, which Colonel O. H. St. John, F.Z.S,, 

 has purchased from its captors at Kandahar and presented to the Society, 

 and to a male Wild Sheep [Ovis cycloceros) , obtained from Afghanistan, and 

 presented to the Society by Captain W. Cotton, F.Z.S. — Mr. A. G. Moore 

 exhibited some eggs of the Red-necked Phalarope, believed to have been 

 taken in England ; and an Egg of the Tree-Pipit, taken near Dublin, this 

 bird having been considered only doubtfully Irish. Mr. More also exhibited 

 a specimen of the Red-crested Pochard, obtained near Tralee, being the first 

 record of the occurrence of this species in Ireland. — Mr. R. Bowdler 

 Sharpe exhibited a specimen of the so-called Sabine's Snipe [GalUnago 

 Sabinii) . This bird had been shot in July last by the Hon. W. W. Palmer 

 at Woolmer Pond, near Selborne, Hants. — Professor F. Jeffrey Bell, 

 F.Z.S., read the fourth of his series of observations on the characters of the 

 Echinoidea. The present paper dealt with most of the genera of the Echino- 

 metridae ; their systematic affinities were discussed and their relations to the 

 Echinidae shown to be so intimate as not to justify their separation into two 

 distinct families. — A second paper by Professor Bell gave the description 

 of a new species of the genus Mespilia, obtained at Samoa by the Rev. S. J. 

 Whitmee, which the author proposed to name after its discoverer, M. Whitmei. 

 — Mr. W. A. Forbes read the fourth of his series of papers on the Ana- 

 tomy of Passerine Birds. The present communication was devoted to the 

 consideration of some points in the anatomy of the genus Conopophaga and 

 of its systematic position. — A communication was read from Professor 

 Newton, F.R.S., in which he proposed to substitute the name Hyposltta 

 for Hypherpes, which he had formerly proposed for a genus of Passerine 

 birds found in Madag-ascar. — A communication was read from Mr. M. Ja- 



