5ß AET. 1. 1. IJIMA : HEXACTINELLIDA, III. 



Here I must turn to a consideration of certain small and 

 young specimens which seem to offer some points of interest. On 

 that most remarkable skeleton of a dead Ghonelasma calyx, which 

 I have had occasion to mention and figure in Contribution I. of 

 this series of studies (Ij., 'oi, pp. 25, 31), I have found, amongst 

 the host of other animals attached to it, five young of the 

 present species in different stages of growth (Sei. Coll. Mus. No. 

 407). Four of these are shown in PI. V., figs. 8 and 9, in 

 natural size. The three specimens to be seen in the latter figure 

 are all globular in shape, each with a small roundish osculum 

 at the upper end. The smallest of the lot measures only 3 mm. 

 in body-diameter. They all sit together on a common, compact, 

 basidictyonal plate of irregular outline and disproportionally large 

 size. The undulating surface of the plate is finely granulated 

 and shows some furrows in it ; below, its substance permeates the 

 underlying Chonelasma skeleton to a depth of 2 mm. or more. 

 There can be no doubt whatever that the plate in question 

 belongs to, and is the product of, the little sponges growing on 

 it. — The fourth specimen, which is not figured, is of an elongate 

 ovoid shape, 9 mm. in length ; the base, only 2 mm. thick, stands 

 out from the center of an irregularly expanded basidictyonal disc 

 of about 9 mm. diameter. — The fifth and largest specimen is the 

 one shown in fig. 8. It has the form of a thick- walled cup, 31 

 nnn. high. The broad base joins the basidictyonal plate — which 

 clasps a parietal process of the Chonelasma and at one place 

 stretches out fully 10 mm. beyond the apparent basal edge of 

 the body proper — making a distinct line of demarcation, which 

 is due to the circumstance that here the loose tissue of the sponge- 

 wall passes abruptly into the rigid reticulum of the plate. — The 

 relatively large size of the basidictyonal plate in the above specimens 



