Mr. C. W. roach on f//c Metamorphosis of a Polijpe-like Animal. 99 



The Cijcluphori {.re of Indian types. Lcptopoma represents 

 forms of the Indian Archijjelago. 



Aulupoma is probably altogether, and Cataulus is nearly con- 

 fined to Ceylon, a species occurring in the Nicobar Isles. 



Pterocyclos is an Indian type. 



November 24th, 1855. 



XI. — Notice of a curious Metamorphosis in a Polype-like Animal. 

 By C. W. Peach, Member of the lloyal Physical Society of 



Edinburgh *. 



[With a Plate.] 



I\ March of the present year, I obtained from a fisherman's line 

 an old and deeply corroded valve of Psammohia ferroensis, hooked 

 up from deep water. On it I observed some minute jelly-like sj)ots, 

 and on placing it in a shallow glass of sea-water and examining 

 it next day with my pocket-lens, I fancied 1 could make them 

 out to be Polype-like animals. I accordingly transferred the shell, 

 in a watch-glass filled with sea-water, to my microscope, and was 

 delighted to find my suspicions correct, for, after a little manage- 

 ment so as to catch the light, I could see the forms as figured at 

 A (PI. VIII.), attached to the shell by short footstalks; they were a 

 little inflated near the upper part, and tipped with a slightly raised 

 and rounded centre, from which extended four long and four 

 short leaf-like arms, each granulated down the centre. One or 

 two had springing from these, delicate tentacle-like arms, as seen 

 at A, a — probably in a farther state of development. They were 

 easily disturbed, but soon again displayed themselves, and their 

 transparency, added to this shyness, rendered it difficult to catch 

 their forms. At first I thought they were the early stage of an 

 Hydractinia, and probably H. brevicornis of jMiiller, mentioned in 

 Johnston's second edition of the ' British Zoojdiytes,' p. 35. 



My next examination was on the 2nd of April, after giving 

 them a supply of sea-water ; they were still fixed ; I could how- 

 ever perceive a difference — the centre of the head was more raised 

 and conical, and the arms shorter. I examined them daily, and 

 on the 6th, instead of moored creatures, I had a fleet of probably 

 more than 100 minute //•<?<? naked-eyed medusoid beauties jerking 

 about in all directions. Except in size they were all alike, and 

 perfectly transparent ; the umbrella was well rounded and pilose ; 

 the subumbrella large; each had four large ocellus-like bulbs, 

 composed of minute dark granules on the edge of the mantle, 



* Communicated by the Author, having been read at the Annual Meeting 

 of the Roval Institution of Cornwall, Nov. 1855. 



7* 



