CHORDATA 241 



in texture patent leather, they having a bright, fine surface. 

 The colour of the species is purple, with the stars a violet- 

 blue. 



A closely similar one is Bolryllus aurolineatus. In this 

 the matrix is purple, and the stars are conspicuous by 

 each individual having a golden line down its centre. 



Very abundant is B. smaragdus. This one forms bulky 

 colonies, sometimes thin and encrusting, but often nodular, 

 of the size of a large duck's egg. The colour is dark green, 

 with the stars a paler or yellowish green. 



B. schlosseri is similar in form and arrangement, but the 

 colour is a beautiful lemon-yellow, with the stars a deeper 

 yellow or orange. In one variety (B. scMosseri, variety 

 Adonis) the individuals have a scarlet line along the centre 

 and a tiny scarlet circle around the mouth. 



B. myosotis, as its name implies, bears a resemblance to 

 our beautiful little flower the forget-me-not. 



B. rubra has stars of bright red on a pale brown ground. 



B. morio is dressed in half mourning. The stars are 

 white, upon a black ground. This is the species shown in 

 the photo (Fig. 100). The other (Fig. 101) is B. schlosseri. 

 These are only a few of our species, a repetition of details 

 would be wearisome, and of no service. 



Allied to Botryllus is a very closely allied genus viz. 

 Botrylloides. The difference between the two genera is 

 readily apparent, even to the casual observer. In this 

 genus the individuals are not arranged in stars, but are in 

 symmetrical double lines, the general cloacal chamber 

 being linear instead of circular. 



I know but of one species on our shores. It is Botrylloides 

 rubrum. The colour is usually orange-red, sometimes 

 crimson, and, rarely, claret. It is of softer texture than 

 the preceding, and it forms encrustations around the 

 stems of fucus, etc., also on stones, but it is most abun- 

 dant encircling the base of the blades of the sea-grass. 



Q 



