ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 677 



New Natal Hydroids.* — E. Warren describes Halocordyle cooper i 

 sp. n., whose special characters appear to be the capitate tentacles 

 which tend to be arranged in whorls and adelocodonic gonophores. 

 Another new form dealt with is Tubularia solitaria sp. n., which appears 

 to have affinities with Corymorpha and with Tubularia, agreeing with 

 the former in the trophosome characters and with the latter in the 

 nature of the gonosome. The presence of an actinnla has decided its 

 inclusion amongst the Tubularise. 



Behaviour of Sea Anemones.f— H. S. Jennings has studied the 

 modifiability of behaviour in sea anemones, but only an abstract of his 

 researches is given. Changes in the internal physiological processes, 

 former stimuli that have affected the animal, former reactions performed, 

 and other factors combine to determine an action. There is a marked 

 tendency in some cases to repeat an action in the way it has been 

 performed before. These various factors give a high degree of com- 

 plexity and adaptiveness to the behaviour of even these low animals. 



Madreporaria Collected by the " Albatross." — T. Wayland Vaughanf 

 reports on a small collection from the Eastern Tropical Pacific, which 

 includes the following new forms : Besmophyllum galapagense, Madrepora 

 galapagensis, Pocillopora diomedem, Bathyactis marenzelleri, Balanophyllia 

 galapagensis, four species of Acropora, and Porites paschalensis. These 

 are all beautifully figured. The author calls attention to the meagreness 

 of our knowledge of the deep-sea Madreporaria of the greater part of the 

 Pacific Ocean. 



Septa of Rugosa.§ — J. E. Duerden finds that the Rugose corals and 

 the Zoanthid Actinians have both a primary hexamerism. The septa in 

 the Rugosa and the mesenteries in the Zoanthese are added in bilateral 

 pairs at only one region, a vertical zone within the primary exocceles, 

 there being four such regions — middle and ventro-lateral chambers — in 

 the Rugosa, and two — ventro-lateral chambers — in the Zoanthese. 



The septa in the Rugosa and the mesenteries in the Zoanthese are 

 never polycyclic, as in modern corals and ordinary Actinians ; at most 

 there are only two cycles of septa, large entosepta and small exosepta, 

 disposed in such a manner as could only have been produced in polyps 

 with a mesenterial arrangement similar to that of the Zoanthese. 



The presence of a ventral directive fossula in the Rugosa, usually 

 persisting in the fully developed and otherwise perfectly radial calice, 

 can be explained by the occurrence within the living rugose polyp of a 

 single ventral siplionoglyph or gonidial groove, such as is characteristic 

 of Zoanthid polyps. 



New Type of Alcyonarian.|| — J. Versluys, jun., describes Bathyal- 

 cyon robmtum g. et sp. n., obtained on the Siboga expedition in the Cerarn 

 Sea from a depth of 1)24 metres. The single specimen looked at first 

 sight like a large solitary polyp, but closer examination showed that it 



* Annals Natal Government Museum, i. (1906) pp. 73-9G (3 pis.). 



f Proc. Acad. Nat. Sci. Philadelphia, lvii. (1905, published 1906) p. 754. 



J Bull. Mus. Comp. Zool., 1. (1906) pp. 61-72 (10 pis.). 



§ Ann. Nat. Hist., xviii. (1906) pp. 227-42 (21 figs.). 



|| Zool. Anzeig., xxx. (1906) pp. 549-53 (4 figs.). 



