, 



25 



My reasons for considering the sponge and rope as one organ- 

 ism are that many of the forms of spicula occurring in the heads 

 of the sponge are also found between filaments forming the rope, 

 particularly the spiculate cruciform, the attenuated rectangulated, 

 hexradiate, and the multihamate birotulate spicules. The occur- 

 rence of long anchoring spicula in Pharonema Graijii and Pharommi 

 Carpenteri is, I should imagine, very conclusive evidence that the 

 rope in Hyalonema is a portion of the head. 



Dr. Gray says he supposes I am not aware that specimens of 

 Hyalonema occur more frequently without than with its parasitic 

 sponge. This is very probably correct ; but they have no doubt 

 lost the sponge, either from the decay of the sarcode, or from 

 being pulled off by the dredger or diver ; in the former case the 

 rope, when divested of its spongy head, would in all probability 

 soon be invested by the parasitic Polythoa. Dr. Perceval Wright, 

 who has had the opportunity of examining specimens in a living 

 state, is quite satisfied as to the parasitic nature of the Polythoa. 



Having thus spoken of the glass rope sponge Hyalonema 

 mirabilis (Gray), I will proceed to give a brief description of the 

 other beautiful and wonderful, but perhaps not so rare, a sponge 

 known as " Venus' Flower Basket," or Euplectella aspergillum, 

 certainly one of Nature's loveliest works. It consists of a 

 tubular body, varying from six inches to a foot in length, and 

 from one to ten inches in diameter, and is composed of a 

 beautiful interlaced network of silicious spicules, with its base 

 enclosed in a thick tuft of silicious basket-work. It is found in 

 the seas of the Phillipine Islands, where it is known as the 

 Regadera or " Watering Pot," and is still supposed by the 

 inhabitants to be the workmanship of a crab, from the fact that 

 one, and sometimes two, crab-like crustaceans are often found 

 shut up in the hollows of the sponges. The lid-like covering of 

 the upper extremity of the Euplectella is the portion of the 

 skeleton last formed, so that the crab must make the sponge its 

 habitation while it is open at the one end, and therefore must 

 remain a prisoner for life, dependent for its subsistence upon any 

 food that may gain entrance through the network of its prison. 



