ECHINODERMATA. 767 
forma tostm, ano marginali, poiis ambulacralibus externis eparsis. C. scutcllaf 
ep. 11 ., Japan. 
Brissus pulmnatus, Philippi, a species from the Mediten-anean, omitted by 
most authors, is a Brissopsis, perhaps identical with B. lyrifera (p. 107). 
Brissus fragilisj of the coast of Norway, is a true Schizaster, very near S. 
canaliferm and S, gihherulus of the Mediterranean (p. 107). 
JIamaxituSy TvoQQ\\.— Tripylus,(jr 2 kj=Faorina, Ahatu8,T, (p. 116). 
Liitken (/. c. p. 118) gives the following arrangement of the 
Spatangid( 2 : — 
A. Fasciola entopetala (et subanalis) present, 
et. F. peripetala wanting : Echinocardiumj Lovenia^ {Gualtieria *). 
/3. F. peripetala present : Breynia. 
B. Fasciola entopetala wanting. 
a. F. peripetala (et lateralis) wanting. 
a. F. subanalis wanting : IlcmipataguSj (Toxastery Enallastevy 
Isaster, Epiaste?'). 
/3. A closed subanal band present : Spatangus, (Micraster), 
b. F. peripetala present. 
a. F. lateralis present, f. subanalis wanting : AgassizWy Schizaster y 
TripyluSy Desoria, Mceray {PeriasteVy Linithia, Prenastc}'). 
/3. F. lateralis wanting. 
t Marginal band also wanting. 
* Subanal band closed : Br'issusy Brissopsisy Kleiniay (^Tox» 
ohrissu^), EiqmtaguSy (PlagionoUm). 
** Subanal band open : Memna, Atropus. 
*** Subanal band quite wanting: AhatuSy Leskiay (Ma~ 
cropncmtcSy Ilomiaster ) . 
ft MarginM band present (snbanal wanting) : Pericosmus, 
Echinus lividus. Stuart (1. c. p. 104) while at Messina studied the deve- 
lopment of this species, especially with regard to the appearance of the mus- 
cular fibres in the larval form. lie refers to three well-distinguished tissues : — • 
1. a simple epithelial tissue, the cells provided with circular nucleoli and beset 
with long thin glistening hairs ; 2. a tolerably strong muscular la 3 ^er, some- 
what of the same structure as that found in some of the Opisthobranchiates ; 
and 3. a well-developed connective tissue. 
Holothurioidea. 
Synapta snrniensisy sp. n., Herapath, p. 5, from Guernsey. Quart. Joum. 
Micr. Sc. 1865. 
Cucumaria digitata. On its occurrence in the Firth of Forth, R. O. Cun- 
ningham, Ann. & Mag. Nat. Hist. 1865, April, p. 355. 
Extinct genera are placed in brackets. 
