MOLLUSCOIDA. 
215 
^imtliiporaj differing from Terehrrpora in having its cells alter- 
nating and carried on alternate axes ; two species are indicated, 
one from the Pacific and one from the Mediterranean. The ex- 
istence of tliis family in both the secondary and tertiary periods 
is also alluded to. 
Paludicella chrenherffi. W. Houghton mentions the occiiiTenco of this 
Polyzoon in the Union Canal, Shropshire, Ann. & Mag. Nat. Hist. vol. xvii. 
18G0, p. 237. Parfitt {l.c. p. 171) describes the statoblasts of this species 
from specimens found near Exeter. 
Proiit (1. c.) describes the following new species : — 
Fenestella nodosa (p. 410), F. dilata fp. 411), both species from the 
Hamilton group ) F. hifurcata (p. 411), geological position and locality 
unknowm. 
Polypora imhricata (p. 412), mountain limestone,' Indiana; P. rigid a 
(p.412). 
Retepora hamiltonensis (p. 412), Hamilton group. 
Ptilodictya {Stictop>ora) variahilis (p. 413), Upper Silurian, Columbus, Ohio. 
Scrialaria helence, sp. n., Giglioli (/. c. p. 132). Vallonia intricata has been 
described by Kutzing and Agardh as an Alga. It was found in considerable 
quantities at Leghorn by the author, and was seen at once to be a Scrialaria ; 
a brief description is given of the nervous system. 
Loxosonia neapolitanuni, sp. n. Kowalewsky (/. c.) describes a now species 
of this strange genus, established for X. singidare by Keferstein. This species 
was found at Naples on the stems of several Pol}^zoa and Hydrozoa. The 
author suggests that it forms the typo of a now family ; an account of its de- 
vclopinoiit is given, nccoinpanied by figures. 
