12 Eoh. 
ECRINODERMATA. 
resemblance to Cystidea. The fourth opening near the peristome of 
Aristocystites , may have been nephridial, as perhaps also, on account of 
its position, the third opening in Echinoencrinus. 
Cu^not (1) describes the anatomy and histology of the Asterids. 
Connective tissue (pp. 3-5). Calcareous tissue (p.6). Muscle fibres (p. G): 
never striated in any way, and never in communication with the cells of 
the ectoderm, as Hamann supposed. Yellow bodies (p. 7), probably 
vegetable cells, occur commonly in sections, especially of the ovoid gland. 
Integument (pp. 7, et seq.) with three layers: peritoneal epithelium (inner- 
most layer) (p. 8) ; external epithelium (outermost layer) (pp. 8, et. seq.') 
consists of indifferent cells, with two kinds of glandular cells, mucous 
cells, and “ cellules mfiriformes.” Colours of starfish due to a pigment 
contained in the cells of the ectoderm. Between the bases of the ecto- 
derm cells is a fibrous layer, the superficial nerve plexus. Fibrous dermis 
(middle layer) (p. 11). Between the dermis and the peritoneal epithe- 
lium is a muscular layer. In Echinaster sepositus there are true dermal 
glands (pp. 11, etseq .), the secretion of which i3 similar to that of the 
“ cellules muriformes.” Skeleton and musculature (pp. 13 & 14) ; the 
name, “ soutien interradiaire,” is proposed for the plate, termed odonto- 
phore by Yiguier. Lymphatic gills (pp. 14 & 17) : the circular lacune at 
the base is not a portion of the “ schizocoele ” (Hamann), but is a closed 
space. Yibratile radioles (p. 17) : these are cylindrical rods, supported 
by a calcareous network in the interior, and covered by columnar ciliated 
epithelium ; they occur on the lateral faces of the marginal plates in 
Luidia and Astropecten. Pedicillariae (pp. 18, et seq.) : Licidia ciliaris has 
both tridactyle and didactyle forms ; the former in specimens from Roscoff, 
the latter in specimens from Banyuls. Asterina gibbosa has pedicillariae 
scarcely differentiated from groups of spines, showing that there is no 
absolute distinction between these two kind of organs. The pedicillariae 
of Asterias glcicialis are then described in detail : (1)“ Cross” pedicillariae 
(pp. 20-22) ; (2) “Straight” pedicillariae (pp. 22 & 23) ; (3) Tridactyle 
pedicillariae (p. 23). ' In the development of the pedicillariae (p. 24) the 
valves appear first, theft the basal piece ; the “ cross ” pedicillariae run 
through a transitory “ straight ” stage. Digestive tract (pp. 31, et seq.) : 
there are two kinds of glandular cells in the epithelium — mucous and 
granular. Hamann’s flask- shaped cells do not exist. Nervous system 
(pp. 44, et seq.): nerve-ring and cords alike formed of an epithelium with 
elongated filamentous cells, between which are found the nervous 
elements, consisting of fibres and cells. The nerve-cells are only bipolar ; 
the multipolar cells, often described, belong to the connective tissue. 
Sense organs (pp. 52, et seq.) : there is no communication between the 
epithelial cells and the nervous layer, as Hamann described. The tentacle 
at the tip of the arm is a tactile organ, and some of the tube feet 
nearest to it are also modified for touch. Eye (pp. 55, et seq.). Blood 
(pp. 63, et seq.) : all the internal fluids, whether of the body cavity, 
blood-vascular, or water-vascular system, have the same composition. 
This internal medium consists of a liquid (sea water) containing sus- 
