Dr. W. C. M'Into.sii on the Zoophytes of St. Andrews. 205 



and lobulated and club-shaped masses of Alcyonium coating the 

 more slender twigs and overrunning the neighbouring Cirri- 

 pedes ; while Obelia fringed most of the branches, here and 

 there giving place to the shorter coating of Sertularia^ stunted 

 Tubularia, or the downy Clytia. Hosts of other animals 

 occurred on the congenial site — tubes of Thelepus and Setpula, 

 Anomia, Saxicava, Xylophaga^ Lepralia^ Cellepora. and Tuhii- 

 lipora representing the sedentaiy forms, sessile-eyed Crusta- 

 ceans and Starfishes the free. Indeed the production formed 

 a compendium of marine zoology that took much time and 

 trouble to investigate. The rapidity of growth of the larger 

 specimens (the Balani being as large as walnuts) was shown 

 by the condition of the wood and bark, and the presence of 

 many delicate twigs. This is also seen in the case of slender 

 branches of the common currant-bushes, which are brought to 

 land in good preservation yet densely fringed with Ohelia 

 longissima and studded with large ascidians. The zoophytes 

 themselves are subject to many parasitic inroads from sponges, 

 Foraminifera, other zoophytes, various Polyzoa, Ascidians, 

 Nudibranchs and their ova, young mussels and Anomice, the 

 ova of Fycnoyonum, Annelids and their tubes (hyaline, gritty, 

 and calcareous), and minute Cin-ipedes. 



In the following list the arrangement and nomenclature of 

 the Eev. T. Hincks in his recen* beautiful work on the 

 Hydroida is adopted. 



Order I. Hydroida. 

 Suborder I. ATHECATA. 



Fam. 1. Clavidse. 



Genus Claya, Gmelin. 



Clava multicornisj Forskal ; Hincks, Brit. Hydroid 



Zoophytes, vol. i. p. 2. 



Frequent under stones in pools near loAV-water mark, and 

 growing on Cynthia grossularia under the cavera roofs ; but 

 it is not seen on the littoral seaweeds, as is Clava squamata 

 on the shores of the Hebrides and the western and other coasts 

 of Scotland. The tentacles show a slightly enlarged sucker- 

 tip. 



Fam. 2. Hydractiniidae. 



Genus Hydractinia, Van Beneden. 



Hydractinia echinata^ Fleming ; Hincks, Brit. H. Z. 

 vol. i. p. 23. 

 Abundant on Fusus islandicus, Natica, and other univalve 

 Ann. d' Mag. N. H. Ser. 4. Vol xiii. 15 



