Molluscoida of St. Andrews. 313 



Family Botryllidae. 

 Genus Leptoclinum, M. Edwards. 



Leptoclinum durum^ M. Ed. ; Forbes & Hanley, Brit. Mollusca, 

 i. p. 17 (as Z. aureunij a misprint). 



Common under stones in rock-pools between tide-marks. 

 Dull yellowish white, with white specks from stellate cal- 

 careous crystals. 



Leptoclinum punctatum J Forbes ; F. & H. Brit. Moll. i. 

 p. 18. 



Not uncommon under stones between tide-marks. 



Genus BoTRYLLUS, Ggertner. 



Botryllus Schlossen, Pallas ; F. & H. Brit. Moll. i. 

 p. 19, pi. A. fig. 7, pi. B. fig. 7. 



Occasionally under stones between tide-marks. The red 

 spot in the centre is not very visible in these specimens. On 

 tearing, a dark brownish digestive system appears. 



Botryllus p>olycyclus J Sav. ; F. & H. Brit. Moll. i. p. 21. 



Frequent near low-water mark on the under surface of 

 stones, on Fuci and Corallina officinalis. 



Genus Botrylloides, M. Edwards. 



Botrylloides Leachii^ Sav. ; F. & H. Brit. Moll. i. p. 23. 

 Common in the laminarian region attached to seaweeds. 



Numerous other species of Botrylloides and a Didemnum are 

 common under stones in the rock-pools. 



Genus Parascidia, Alder. 



Par ascidia Fleming ii^ Alder, Ann. & Mag. Nat. Hist. 

 1863, xi. p. 172, 



Occasionally on laminarian roots near low water. Mr. 

 Alder was of opinion that the drawing represented a young 

 form of tliis species. It consisted of cylindrical animals with 

 a transparent investment. On the summit of each are several 

 long, ovate, reddish orange structures marked with yellowish 

 white grains, showing at the free extremity an oral aperture 

 surrounded by eight small papilla?. 



