102 GUIDE TO THE AUSTRALIAN MUSEUM. 



kidney-shaped lobe, or disposed in a terminal cluster. Examples — 

 Pennatula rubra, P. phosphoi'ea, Sarcojihyllum gr ancle, Clavella 

 australasict, Renilla re7iiforniis, and Osteocella verrillii, the last 

 being about six feet in length. (See Case 17.} 



3. The Gorgoniidas are mostly large branched polyps with 

 a horny or calcareous axis surrounded by a thin layer of flesh, in 

 in wliich the polyps are imbedded ; the whole of the fleshy substance 

 is often charged with spicules. Rhipldogorgia Jlahellum, Xiphogor- 

 gia anceps, Verrucella gemmacea, Mopsella coccinea, Melithcea 

 ochracea, Primnoa ansiralasice, Isis, sp., and Corallum rubrum, 

 the last being the well-known red coral of commerce, may be 

 mentioned as examples. (See Case 15.) 



4. The TubiporidSB or Organ Corals, usually form large masses 

 of a bright red colour, consisting of a vast number of calcareous 

 tubes connected by horizontal plates. Example — Tubipora 

 musica. (See Case 15.) 



Division III.— PORIFERA. 



Class VL— PORIFERA or Sponges.— In this division the 

 body has a spongy consistence, and is strengthened by a calcareous, 

 siliceous, or horny skeleton. There is a series of inhalent pores 

 passing from the outside to the inner ciliated passages, and one 

 or more eihalent apertures. The water passes in by means of 

 the former, and out by the latter, the movement being caused by 

 the action of the flagellate cells lining the body cavity. 



The Collections, which include very many of the types collected 

 by the Museum stafl" in Port Jackson and described by Dr. R. 

 von Lendenfeld, are to be seen in Cases 18 and 19. 



The Myxospongia are represented by Bajalus laxus, which 

 is a soft gelatinous sponge without hard parts or skeleton. 



The Calcispongia are represented, among others, by 

 Sycandra arborea, and >S'. ramsayi ; the former exhibits tree-like 

 clusters with cylindrical branches and a smooth surface, tlie latter 

 rounded sac-like bodies clothed with long calcareous spicules. 



The Siliceous Sponges are represented by the Euplectella 

 aspergillum, or Venus's Flower basket; and by Ilyalonema 

 sieboldii, or Glass Rope Sponge from Japan, which has the upper 



