96 Proceedwgs of the Royal Socidi/ of Victoria. 



The sponge which formed the subject of my own investiga- 

 tions, is the remarkable form originally named by Carter 

 TeicJtonella lahyTintkica. I propose shortly to publish a 

 full account in another place of the anatomy of this sponge ; 

 meanwhile it is necessary to state that it does not belong to 

 the genus TeicJtonella at all, but is a true Sycon — a fact, 

 indeed, which Mr. Carter himself recognises in one of his 

 later papers,* wherein he suggests that its generic name 

 might be changed from TeicJionella to Grantia. The 

 sponge consists of a stalked cup, with a thin and very much 

 folded wall. The flagellated chambers penetrate the walls of 

 the cup in a direction at right angles to the two surfaces and 

 open on the inner surface into the widely expanded cavity, 

 corresponding to the gastral cavity of a typical Sj'con ; the 

 osculum being enormously large and bounded by the folded 

 margin of the cup. 



I do not wish here to discuss the generic nomenclature of 

 this sponge, which question I reserve for consideration in 

 my forthcoming paper ; but as it certainly cannot be called 

 TeichoneUa, the type species of which I find to be a typical 

 Leucon, I will, piovisionally at any rate, adopt jVJr. Carter's 

 suggestion and call it Gitiutia lahyvinthica. 



In a fine specimen of Grantia lahyvinthica, di-edged by 

 Mr. J. Bracebridge Wilson at Easter 1888, whilst I was 

 myself with him, I met with a very large number of 

 embryos. These were found both in the maternal tissues and 

 also lying free in the flagellated chambers. While still within 

 the maternal tissues the embryo lies in a cavity, which is 

 but little larger than itself and lined by a very distinct 

 single layer of flattened endothelial cells {vide Fig. 1). 

 This capsule always lies in the thin layer of mesoderm 

 between the wall of a flagellated chamber and the layer of 

 spicules which surrounds it. Hence the capsule is bounded on 

 the outside by the soft and yielding wall of the flagellated 

 chauiber, and on the inside by a layer of rigid spicules. 

 As the embr5^o increases in size the capsule in which it lies 

 becomes correspondingly enlarged, and owing to the manner 

 in which it is bounded this enlargement must take place 

 towards the flagellated chamber. Thus the side of the 

 capsule next to the layer of s])icules becomes flattened, while 

 the opposite side bulges out into the flagellated chamber 

 and forms a kind of blister, over which the delicate wall 



* " Annalf? and Magazine of Natural History," July 1886, p. 38. 



