84 ANTHOZOA HYDROIDA. 



tentacula, M. de Quatrefages tells us that he has found true 

 ova in the substance of the common horny base, situated prin- 

 cipally near the insertion of the polypes thereon, and at the 

 roots of the elevated spines which roughen its surface. He 

 conjectures that these eggs escape from their seminal bed 

 through the spines, which are supposed to be hollow and 

 open at the top. (Ann. des Sc. Nat. xx. p. 242-3.) The 

 correctness of these observations may be doubted. 



1. H. ECHINATA, basal crust muricated : polypes white, the 

 body elongate, clavate above and furnished with numerous 

 rather short tentacula. Greorge Montagu. 



PLATE I. FIG. 46. 



Alcyonium echinatum, Flem. Brit. Anim. 517. Johnston in Trans. Newc. Soc. ii. 

 251, pi. 9, fig. 2. Blainv. Actinolog. 525. Gray in Zoologist, i. 204. Gould's 

 Massachus. 351. Alcyonidium echinatum, Johns. Brit. Zooph. 304, pi. 42, fig. 

 3, 4. Couch Corn. Faun. 134. Coryne squamata, var. Johns. Brit. Zooph. Ill, 

 pi. 2, fig. 4,5. Couch Corn. Faun. 12, pi. 1, fig. 2. Echinochorium clavigerum, 

 Hassall in Ann. and Mag. N. Hist. vii. 371, pi- 10, fig. 5. Macgillivray in Ibid, 

 ix. 463. Hassall in Ibid. xii. 117. Coryne Hassalli,Fo/-6e* in Ann. N. Hist.xii. 

 189. Hydractinia lactea, Van Beneden Les Tubul. 64, pi. 6, fig. 7-14. Ann. N. 

 Hist. xv. 250. Synhydra parasites, Quatrefages in Ann. des Sc. Nat. xx. 232, 

 pi. 8 and 9. 



Hob. On old univalve shells from deep water ; not uncommon, 

 and generally distributed. 



Mr. John Macgillivray tells us that, in the neighbourhood of 

 Aberdeen, this zoophyte is " of frequent occurrence on Buccinum 

 undatum, Fusus antiquus, and F. corneus, brought up by the fishing- 

 lines." It is found similarly situated on all parts of the British 

 coast, growing in clusters of a milk-white colour on the shell. The 

 polype is about the quarter of an inch in height, and its filiform 

 stalk or pedicle gradually passes into a clavate head, which is 

 surrounded, under the apex, with an irregular series of short ten- 

 tacula. These vary in number : the figures of Professor Forbes 

 represent individuals with from three to ten ; tbose figured by us, 

 in tbe first edition of this work, had from twelve to fifteen ; and, 

 according to Mr. Hassall, tbey frequently amount to between twenty 

 and thirty, and are somewhat club-shaped ; a shape that depends 

 on their degree of contraction. The ova are simple, or have only a 

 single vitellus, and the opake part is yellowish : ' les ceufs en 

 grappe avec le sinus jaune." Van Beneden. 



The crust secreted by the polypes, and which associates them 



