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ASCIDIANS OF GUERNSEY. 



I. — Drepanophorus rubrostriatus is a small worm that lives in the 

 interior and which swims in and out of either orifice indiscriminately. 

 Mr. F. Wright was, I believe, the first to record it as living in Ascidia. 



II. — Nolodelpln/s ascidicola, a small one-eyed crustacean, lives in the 

 branchial sac. 



III. — Mr. F. Wright, late of the Guille-Alles Library, discovered a 

 true external parasite. It is a crustacean whose front legs are developed 

 as formidable clasping organs. It has not yet been identified. 



This species of Ascidian is easily kept in an aquarium where its 



habits can be easily studied. 

 C. pulehella (Alder). Guernsey, dredged (Norman). Body elongated, 



cylindrical, and of a red colour. It is highly retractile. 

 C. eanina (Midler). Bordeaux (Fleure). Lihou (Sharp). Colour brown, 



mantle vermilion. Attached at one end by short processes of the test. 

 Family IV.-CLAVELINIDiE. 



Simple Ascidians reproducing by gemmation to form colonies. Each 

 individual with a distinct test, but all communicating by a common blood 

 system contained in a creeping stem or stolon. Tentacles simple ; branchial 

 sac not folded ; stigmata straight. 



Diazona hebridiea (Forbes and Goodsir). Guernsey, deep water (Alder and 



Norman). Colony massive, with individuals arising from a massive base. 



They have no pigmented circle round the siphons. 

 Clavelina lepadiformis (Mutter). Guernsey and Herm (Alder). Lihou, 



Pea Stacks, Bordeaux, &c. Common (Sharp). 



Forms beautiful, erect transparent vases streaked with yellow or 



brown lines. 



C. Rissoana (Milne-Ediv.) Bordeaux (Sharp). 12 to 16 rows of stigmata; 



white lines of pigment on thorax. 

 Perophora listeri (Wiegm.) Bordeaux, Lihou (Sharp). The colonies look 



like beds of cooked tapioca. 



Sub-Order II. — Ascidi/e Compositi/e (Savigny). 

 Family I.— BOTRYLLIDiE (Giard). 

 Ascidiozooids short and not divided into regions. Colony usually thin 

 and incrusting. Systems circular, elliptical, or forming branched lines. 

 Test usually soft ; branchial sac well developed, internal bars predent, stig- 

 mata numerous. 



BotryllUS smaragdus (M.-Edw.) Common in Guernsey (Sharp). Alder- 



ney. Matrix dark green, stars pale green. 

 B. Violaeeus (M.-Edw.) Common in Guernsey (Sharp). Alderney (Sharp). 



Stars and matrix blue with white lines. 

 B. rubigO (Giard). Bordeaux (Sharp). Brown, with red marks. 

 B. aurolineatUS (Giard). Bordeaux, L'Islet, Havelet Bay (Sharp). Brown 



with white and red markings. Ascidiozooids 2§ mms. 8 to 10 in system. 

 B. myosotis (Giard). Havelet Bay (Sharp). This one resembles the familiar 



forget-me-not. 



B. bivittatUS (M.-Edw.) Lihou (Sharp). Matrix ash-grey, individuals 



with two yellow rings round mouth and cloaca. 

 B. morio (Giard). Common in Guernsey (Sharp). Alderney (Sharp). 



Matrix black ; stars white. 

 B. gemmeus (Sav.) Lihou (Sharp). Matrix violet-grey ; stars yellow or 



greyish-gold. Systems widely separate. 

 B. polyelyelus (?). Lihou, Yazon (Sharp). Matrix grey; stars bluish or 



purple. 



Botrylloides rotifera (M.-Ediv.) Lihou and Alderney (Sharp). Yellow 

 with red marks. 



