214 Dr. W. C. M'lntosh on the Zoophytes of St. Andrews. 



deep water of the bay. Mr. Alder correctly observes that this 

 form leads us to Thuiaria. 



Geinis Hydrallmania, Hincks. 

 Hydrallmania falcatay L. ; Hincks, Brit. H. Z. vol. i. p. 273. 



One of the most abundant hydroid zoophytes from the coral- 

 line ground. Its form varies from the elongated spiral to the 

 broadly branched condition, and it is frequently loaded with 

 parasitic zoophytes, both horny and calcareous. It is also a 

 favourite site for Nudibranchiate Mollusca and their ova, and 

 minute Annelids construct their tubes on every convenient 

 bough. Young specimens are plentiful also under stones 

 between tide-marks, where their habit differs considerably from 

 the foregoing, having the form of a simple straight pinna, 

 generally coated with parasitic structures, both animal and 

 vegetable. 



Genus Thuiaria, Fleming. 



Thuiaria thuja, L. ; Hincks, Brit. H. Z. vol. i. p. 275. 



Common ; chiefly frequenting dead valves of Cyprina., 

 Pecten, and Tapes, as well as stones, shooting its long stems 

 upwards (occasionally to the length of 14 inches) amidst 

 masses of the tubes of Serjnda, Thelepus, and other Annelids, 

 and patches oiAIcyonium. In some examples a short secondary 

 stem branches from the main trunk near the base. Parasitic 

 upon the stems are numerous other corallines, such as Diphasia 

 rosacea, which clothes anew the bare zigzag trunk with a more 

 silky fringe than nature originally provided ; rough crusts of 

 Cellepora or the spreading Alcyonium SLiidAIcyonidium entirely 

 surround it ; while occasionally a long tunnel of Thelepus is 

 glued from the base to the branching portion. Now and then 

 it occurs in the stomach of the cod. 



Fam. 9. Plumulariidae. 



Genus Antennularia, Lamarck. 



Antennularia antennina, L. ; Hincks, Brit. H. Z. vol. i. p. 280. 



From the deep water of the bay ; common, but less so than 

 the next species. Fine tufts reach a height of fully 1 1 inches. 

 In a curious example a number of simple straight stems pro- 

 ceed from the upper edge of a fragment of an old trunk. 



Antennularia ramosa, Lamarck ; Hincks, Brit. H. Z. 



vol. i. p. 282. 



Common in deep water, whence it is usually brought by the 

 fishermen's lines. 



