252 Rev. T. Hincks's Catalogue of Zoophytes 



3. H. tenellum, n. sp. Plate VI. figs. 1-4. 



Polypary of extreme delicacy ; stem simple or very slightly 

 branched, smooth, zigzag, bearing a cell at every bend, run- 

 ning out at the extremity into long tendril-like fibres, which 

 give off a few short ramulij cells gracefully everted at the 

 margin, often of considerable length, — in most cases a num- 

 ber (frequently four or five) rising one from within another, 

 and marking the successive generations of polypes. Gono- 

 thecae sometimes broadly ovate, sometimes elongate and 

 pointed, borne on short pedicles and occurring singly. Height 

 of fine specimens about % of an inch. 



Abundant on Salicornaria farcimino'ides, Salcombe Bay. 



This very beautiful species is remarkable for its extreme te- 

 nuity and delicacy. The character of the stem is peculiar : it is 

 made up of a number of straight portions, each terminating in 

 a cell, which spring one from the £ther at the base of the cells, 

 and bend alternately to opposite sides. There is a slight crena- 

 tion of the stem just above each cell. A simple cell is rarely 

 met with on mature specimens. Generally the polype protrudes 

 from the uppermost of a pile of little cups with prettily everted 

 rims, which fit one into the other and form a branchlet of some 

 length. 



The gonothecse are of two forms, one somewhat broadly ovate, 

 the other slender and tapering. The former contains a large 

 sporosac, in which a single (?) ovum is produced. The latter is 

 probably the male capsule*. 



2. Sertularia, Linn. 

 1. S. polyzonias, Linn. 



Very common : on rocks near low-water mark ; dredged, on 

 other zoophytes, Ascidise, stones, &c.,in 15-20 fathoms ; amongst 

 the trawl-refuse. It presents many varieties of size and habit. 

 When living, it is of a bright straw-colour, and is certainly one 

 of the prettiest, as it is one of the commonest and most widely- 

 distributed, of the Sevtularian Hydrozoa. 



2. S. Gayi, Lamouroux, Expos. Meth. 12. pi. 66. figs. 8, 9. 



Not uncommon in the Coralline zone ; amongst the refuse of 

 the Plymouth trawlers, fine ; on Pinna from a depth of GO fa- 



* I have already pointed out that the male and female capsules are of 

 different form in H. halecinum and H. Beanii (Rep. of Brit. Assoc, for 1858). 

 In the latter species the sperm-capsules are elongate-ovoidal, the calceoli- 

 form capsules producing the ova. In H. halecinum the male gonothecse 

 are simply ovate, wanting the tubular process at the top which distinguishes 

 the female. The same difference seems to exist in the present species. 



