with some Remarks on the Nature of the Spongise Marinae. 373 



their fixed* localities in the cells or pores of the Sponge, I deposited them in 

 a china dish nearly filled with water, which I renewed twice a day. I was 

 most attentive in examining not only with my naked eye, but also with a 

 powerful lens, whether these bodies possessed any spontaneous motions, but 

 could not discover the least appearance of any ; on the contrary, the instant 

 they were put into the water they sunk to the bottom of the dish ; there 

 remaining motionless, most of them commenced to germinate, and became 

 permanently fixed. Several of these seedlike bodies being of different sizes, 

 I found that some began to grow sooner than others, probably by reason of 

 their being in a more mature state. The manner of germination, according 

 to my observation, is this : when the seedlike body has lain a sufiicient time 

 in the water, a very small quantity of a soft opake substance appears sponta- 

 neously protruding from its apex or orifice at its top ; it is of a pure white 

 colour, and soon glues the seedlike body to the dish ; this substance gradu- 

 ally increases, and sometimes entirely enveloping the parent body, continues 

 spreading over whatever object it has attached itself to. At first there are no 

 distinct traces of the Sponge itself, but only a white thick gelatinous matter, 

 like a piece of wet cotton-wool, is all that is to be seen : this, however, when 

 allowed to dry, will exhibit the thin membrane of the Sponge, and the oscules 

 and cells or pores formed by the interlacing and crossing of the young fibres 

 with the sharp and prominent spicula. As a few of these bodies, after several 

 days, did not germinate, I squeezed them sufficiently hard so as to break their 

 envelopes or shells, and pressed out a little of the inner opake substance, 

 which then very readily grew and enlarged. 



Having thus clearly proved that this Spongilla, is capable of being repro- 

 duced or grown both from its fixed seedlike, and from its locomotive germ- 

 like, bodies tj it therefore is to be further inquired concerning the real nature 

 of them. 



* M. De Lamarck is wrong where he has defined these bodies as " granula phirima gelatinosa non 

 affixa in cellulis." (An. sans Vert. torn. ii. p. 98. edit. 1816.) But M. Dutrochet thus correctly de- 

 scribes tlie like bodies in the Spongilla lacustris : " corps oviformes de couleur jaune, et qui adh6raient 

 au tissu fibreux." (p. 206.) Again, at p. 211, he says, " les fibres les plus grosses auxqueUes 6taient 

 fixes d'innombrables corps oviformes." See Annal. des Sci. Nat. torn. xv. 



t It perhaps seems inconsistent to say that the Sponge may be reproduced from both these bodies. 

 But I will thus explain it : the fixed seedlike body contains within it a somewhat transparent jelly 



