ZOOPHYTOLOGY. 129 
seas. (Vid. ‘ Annals Nat. Hist.,’ 2d ser., vol. xviil., p. 34, 
pl. i., fig. 6.) 
2. Fam. Cristapm. 
Two species of Crisia, one of which appears to correspond 
with C. dentata in a dwarf state, and the other to be as yet 
undescribed, will be figured and described in a subsequent 
number. 
HypDkRozoa. 
Fam. SERTULARIAD. 
1. Gen. Sertularia, Linn. 
1. S. disticha, Bose. 
Hab. Madeira (on fucus), Johnson. 
S. disticha, Bosc., ‘Vers,’ 2d ed., t. iii, p. 121, pl, xxi, fig. 2; La- 
marck, ‘ Hist. d. An. s. V.,’ p. 154. 
Dynamena disticha, Audouin, ‘Expl.’ I, p. 244; Savigny, ‘ Egypt,’ 
pl. xiv, fig. 2; Lamouroux, ‘ Hist. d. Cor. flex.,’ 
p- 181; Blainville, ‘ Act.,’ p. 484. 
Dynamena distans, Bose, op. cit., p. 121; Audouin, ‘ Expl.,’ p. 243 ; 
Savigny, ‘ Egypt,’ pl. xiv, fig. 1. 
There appears to be no sufficient reason, from anything 
which appears in the excellent figures of Savigny, why 
D. disticha and distans should be separated. They both 
occur on the Gulf-weed. 
2. S. polyzonias, Linn. (in part). (Ellis, ‘ Corallines,’ pl. ii, fig. B. ; 
S. Ellisiit, M. Edw. in Lamarck’s ‘ Hist. d. An. 
s. V.,’ 2d ed., £. ili, p. 142.) 
We are indebted to Mr. Alder for the distinction from 
S. polyzonias (Linn. et Auct.) of a species having only three 
denticles or angles on the mouth of the cell, in place of four 
which may almost always be distinguished in S. polyzonias. 
This species, under the name of S. tricuspidata, is described 
and figured in his Catalogue of Zooph. of: Northumb. and 
Durham’ (p. 21, pl. ui, figs. 1, 2). An additional character, 
however, might perhaps be appended to those there given 
as distinguishing S. tricuspidata from S. polyzonias, the 
absence, viz., of four denticles from the mouth of the ovicell, 
both male and female, which always exist in S. polyzonias. 
Besides this, however, there seems reason to believe, not- 
withstanding Dr. Johnston’s weighty authority on the other 
side, that M. Edwards was right in suggesting that S. 
polyzonias should be divided into two species, also distin- 
cuished by the presence and absence of the denticles at the 
mouth of the ovicell. In the form for which he proposes the 
name S. Ellisit, the ovicell is clearly represented by Ellis 
