$ 52. 
“TLis metamorphosis is completed when the skin is 
«covered by a brown and solid layer, and new indi- 
viduals are developed by gemmation from the two 
Polyps (See Meyen, Isis, Joc. cit.). I have seen 
the development of the coralla of Cristatella mi- 
vabilis and Plumatella campanulata occur in 
the same way. With the Cristatellae,gemmae of 
new Polyps are often seen to arise from the skin, 
even after the escape of the two Polyps, and before 
the young colony has become at all fixed. At this 
epoch of development these Polyps have been taken 
by Cuvier for a distinct species, and called Crista- 
telia mucedo. See Roesel, loc. cit. p. 659, Taf. 
* [§ 62, note 8.] The embryonic development 
-of the Bryozoa has been carefully wrought out by 
Wan Beneden. See Recherch. sur les Bryozoaires, 
THE POLYPI. 
57 
XCI.; and Dupin, Ann. d. Sc. Nat. VII. 1837, p. 
65, pl. II. and ITT. 
Infusoria-like embryos have been observed also 
by Steenstrup (Untersuch. loc. cit. p. 66, Taf. I. fig. 
21) with Coryne squamata, and by Sars (Faun. 
littoral. Norveg. p. 7, Tab. II. fig. 7-11) with Po- 
docoryna carnea. The round eggs moving about 
by means of cilia, which Reid (Ann. of Nat. Hist. 
XVI. p. 392, 397, pl. XII. fig. 9, 18) has observed 
in the visceral cavity of Pedicellina echinata, 
and in special capsules with Flustra avicularis, 
were probably embryos also.* 
&c., Mém. Acad. Bruxelles. XIX. See also Alle 
man, Report, loc. cit. 1850, p. 322 — Ep. 
