IN THE MUD OF THE LEVANT. 2? 



points, like grappling irons. The skin, or outer 

 crust, is dry, and consists of an aggregation of 

 small siliceous globules, cemented together by an 

 organic mucus, so as to form a solid pavement. 

 Each globule, both in the living species and in 

 those from the Levant, is delicately reticulated. 

 Fig. 42 represents one of the round spicula, and 

 Fig. 43 is probably one of the radiating ones from 

 the same sponge. Fig. 48 represents a form in 

 which the surface is armed with symmetrical rings 

 of minute points. I have observed it in sponges 

 from our English coast, from the Mediterranean 

 and West Indian Seas, and also along with 

 other organisms in the Ichaboe guano. I have 

 occasionally seen an analogous muricated form in 

 which the small points were dispersed irregularly, 

 instead of being arranged in transverse rings. 



Fig. 49 is a portion of a very large calcareous 

 spiculum in which the surface is covered with 

 irregularly arranged projections, or flattened pa- 

 pillae, which preserve, however, a little tendency 

 to a spiral arrangement. I have seen forms 

 somewhat similar in sand from the West Indies. 

 I suspect they belong to some of the Eolidse so 

 beautifully illustrated by Messrs. Alder and 



