132 UEPOET — 1872. 



It is scr.rcely correct to regard the central mass of protoplasm as a true stomach. 

 The author had failed to find any evidence of a permanent gastric or somatic cavit_y ; 

 nnd he reo-arded the protoplasm mass to which the gullet leads as representing the 

 "parenchyma" of the Infusoria, and, like this, allowing of the solid food being 

 forced down into it from the gullet and there encysted in extemporaneously formed 

 vacuolre. The food also frequently forces its way from the central mass into the 

 radiating processes ; and diatoms and other microscopic organisms may be seen in 

 these processes enclosed in cyst-like dilatations of them, extemporaneously formed 

 for their reception at various distances from the central protoplasm. 



It was considered probable that the canal which seems to exist in the superficial 

 i-idi'-e artbrds exit for certaiu efiete matters, which may be conveyed to it through 

 the process by which it is kept in connexion with the central protoplasm. 



Our knowledge of the phenomena of reproduction and development in Nodihica 

 is still very imperfect, and the authoi" saw little which seemed capable of throwing 

 additional" light on this subjeci. He regarded it, however, as probable that the 

 nucleated cell-lilce bodies which are present in the peripheral layer of protoplasm 

 have a reproductive function, and are destined after liberation to become developed 

 into new individuals. 



From the account now given it will be apparent that Xoctihca consists essen- 

 tially of an enormously vacuolated protoplasm, involving a nucleus and enclosed 

 in a'structureless sac, the vacuolation taking place to such an extent as to separate 

 the contents into a peripheral layer of protoplasm which remains adherent to the 

 outer sac, and into a central mass which is kept in communication v,-ith the peri- 

 pheral layer by processes of protoplasm which pass from one to the other. The 

 author believed that the nucleus of A'uctiluca had a significance difierent from that 

 of the so-called nucleus of the ordinary Infusoria, and that it admitted of a closer 

 comparison with the true cell-nucleus. lie was of opinion that the nearest ally of 

 NucW.Kca would be found in the somewhat anomalous infusorial genus Pcrklinia. 



hi conclusion the author detailed some observations he had made on the lumi- 

 nosity of Noctiluca ; and he gave reasons for maintaining that the seat of the phos- 

 phorescence is entirely confined to the peripheral layer of protoplasm which lines 

 the external structureless membrane. 



Oil tlie Siiiic'ure of Ed^va^dsia. Uy Prof. Allman, F.R.S. 



The structure of this beautiful little Actinozoon differs in many important points 

 from that of both the Zoautharian and Alcyonarian polypes. It was shown that 

 just within the mouth the walls of the stomach-sac project into the cavity of the 

 sac in such a way as to form eight complicated frill-like lobes — that the eight 

 vertical radiating lamellae which project into the body-cavity from the outer walls, 

 and are composed of parallel longitudinal fibres enclosed between two membranous 

 layers, do not reach the stomach-sac in any part of their course — and that eight 

 strong muscular bundles pass symmetrically through the whole length of the body- 

 cavitjs being attached at one end to the disk which carries the tentacles, and at 

 the other to the floor of the body-cavity, while they are free in their intervening 

 course. 



Attached along the length of about the posterior half of each muscular bundle is 

 the long sinuous generative baud, with its chord-like craspedum loaded with thread- 

 cells. Just before terminating at the lower opening of the stomach-sac each of the 

 eight generative bands enters a most remarkable pectinated organ, which appears to 

 be quite rmrepresented in any other group of the Crelenterata. It was difficult to 

 suggest the true significance of these organs ; their relation to the generative bands 

 might lead to the belief that they are testes, or they maybe analogous to the so-called 

 cement-glands v,'hich exist near the outlet of the oviducts in some of the lower 

 animals. In this case they might supply some additional investment to the ova 

 at the time of extrusion. 



The author regarded Edwardsia as presenting a very distinct type of actinozoal 

 structure, whicli occupies an intermediate position between that of the zoantharian 

 and that of the alcyonarian polypes. He also compared it with the extinct rugose 



