456 RECOKD OF CURRENT RESEARCHES RELATING TO 



cells. If a specimen of Sagartia be taken and the cpithelio-musciilar 

 layer stripped oflf, lacunte and clefts will be found in the lamella 

 thus obtained, and between their margins there will be found a 

 number of fine fibrils ; these are the nerve-fibres. To see the ganglia 

 it is necessary to wash away part of the epithelium from the septa of 

 specimens which have been hardened [Anthea is better than Sagartia 

 for this purpose); there will now be seen delicate filaments which 

 take a more or less perpendicular direction to the subjacent muscular 

 fibres, and in the bundles of these nerve-filaments or connected with 

 them by processes we find ganglion cells ; some are excessively small, 

 others appear to be well filled with protoplasmic contents ; they vary 

 greatly in form, but their distinct nuclei generally contain a large 

 nucleolus. 



As to the arrangement of the septa, having lately dealt with 

 this subject,* we must content ourselves with drawing attention to 

 the authors' conclusions ; they find that all the septa of the Actinias 

 are arranged in pairs, but that the first twelve, which arise from 

 four equidistant points, are somewhat distinguished from the rest ; 

 from two opposite points arise successively two pairs, and from the 

 two intermediate points (opposite to one another) only one pair. 

 The other septa (secondary septa) arise in pairs and form cycles, 

 each of which contains the same number of septa as all those 

 which have gone before, and then, if they have any connection with 

 the wall of the oesophagus, have only an incomplete one. They are 

 always provided with 



Generative organs. All the species examined had the sexes 

 separate ; the organs are placed in that part of the septum which 

 lies internal to the strong fibrous bands of the longitudinal muscles, 

 but the musculature of the septa is, at the points where the 

 genital organs are developed, strong in an inverse proportion to 

 the development of these parts. The male and female organs are 

 both formed on the same type, and consist of follicles set in trans- 

 verse rows ; the mother-cells of the spermatozoa are described as 

 occupying the periphery of the follicles while the matured sper- 

 matozoa are aggregated together and form radiating rows which 

 pass backwards towards the periphery from the point at which they 

 will, later on, be extruded. The ovarian cell appears to be attached 

 to the surface of the epithelium by means of a finely striated process ; 

 this stalk appears to be the means by which the egg-cell obtains its 

 nutriment, but the surrounding endodermal epithelium is also of 

 importance in this particular ; there may be separated from this, very 

 long cells which are filled with highly refractive granules not of a 

 fatty but of, apparently, an albuminous nature. On the interesting 

 question of the origin of the generative organs the authors remark 

 that, in the adult condition, these lie in the mesoderm, while the fact 

 that the ova are enclosed between two endodermal layers and have 

 no connection with the ectoderm, leads to the supposition that they 

 are of endodermal origin; and this derivation appears to be truly 



* This Journal, ii. (1879) p. 893. 



