COMPOUND ASCIDIJ3. 131 



numerous on our shores; but the most varied forms 

 are taken only by the dredge. Still, on the stems of Sea- 

 weeds, within tide-marks, especially on the various kinds 

 of Cystoseira, and on the Laminarice, numerous kinds, 

 some of them extremely beautiful, may be found. The 

 stems of the Olive-coloured Sea-weeds are often literally 

 concealed by clasping masses of firm jelly, whose sur- 

 face is marked with radiating stars, blue, crimson, or 

 orange, or various in colour, resembling a tesselated 

 pavement, or the polished section of a Torquay madre- 

 pore-stone. These belong to the 

 animals in question, and to the 

 tribe Botryllidoe. The gelatinous 

 crust is a matrix common to the 

 whole community; while each 

 star that glitters on its surface 

 consists of numerous separate in- BOTRYIXOB. 



dividuals, similar in most points 

 of their structure to the bag-like Ascidice. It is im- 

 possible, without colour, to do justice to such delicate 

 creatures by a figure, and the wood-cut in the margin 

 is merely intended to guide the eye. A brief outline 

 of what is known of the British species of this highly 

 curious family is given in the first chapters of Forbes 

 and Hanley's " British Mollusca," to which I must refer 

 for further information : but a more complete history, 

 accompanied by coloured figures, is required before 

 the study of these curious creatures can be rendered 

 popular. 



These Ascidians are among the humblest members 

 of the great class of MOLLUSCA. This class includes the 



