394 EVENINGS AT THE MICEOSCOPE. 



excellent naturalists — as Dujardin, Steenstrup, Dalyell, 

 Loven, and others — it appears that this beautiful and 

 elegant little Polype gives birth to medusa-shaped 

 young. Contrary, however, to the rule in Laomedea, 

 the Medusa is in this case pushed forth as a bud 

 from the side of the club, without any protecting cap- 

 sule. The process is exceedingly like a plant develop- 

 ing a flower; for the bud grows until it at length 

 expands blossom-like, and a beautiful little umbrella- 

 form Medusa is seen adhering to the Polype. At 

 length the brilliant little living flower becomes detach- 

 ed ; and, after swimming freely for a time, discharges 

 ova or gemmules from its ovaries, which develop into 

 a creeping-root-thread, and finally into the club-headed 

 threads of the Stauridia. 



Some objects which I have to exhibit to you are 

 altogether unique as to their appearance ; and, if you 

 are not as imperturbable as a philosopher of the ^Toa, 

 or a Mohawk Indian, will certainly excite both your 

 risibility and your wonder. For some little time I have 

 been keeping in this tank a specimen of that rather rare 

 and very interesting Sdbella, the Amphitrite vesiculosa 

 of Montagu.* You see it is a worm, inhabiting a sort 

 of skinny tube, much begrimed with mud, about two 

 inches of its length being exposed ; the remainder, or 

 about as much more, being concealed among the sand 

 and sediment of the bottom. 



A beautiful object is presented by the gill-fans of 

 this worm. These organs are always elegant, whatever 

 species of the genus is befoi-e us ; l3ut here, in addition 

 to the charm of the slender filaments, so delicately 

 fringed with their double comb-like rows of cirri, the 

 * Linn. Trans, xi. 19. 



