a HERAPATH, ON THE GENUS SYNAPTA. 
vestigations into the constant characters of the pedicellariz 
of other echinodermata, it is highly probable that full re- 
liance can be placed on these calcareous bodies for specific 
characters. 
In the first place, it may be as well to summarise the posi- 
tion of Synapta in the zoological scale, remarking that, to 
keep strictly to the method of arrangement adopted by 
Professor Forbes, Synapta should be removed from the Holo- 
thuriade and placed in the vermigrade order—as no pedal 
rows of ambulacral cirrhi exist, and there are no appear- 
ances of any protusile branchial organs—Echinodermata— 
order, vi, vermigrada. 
Family, SYNAPTIDE. 
Body cylindric, vermiform, without suckers, and destitute 
of sipuncular prolongation ; mouth surrounded with tentacula, 
elongate, pinnate or digitate; calcareous plates in external 
skin. (See Plate I.) 
Genus, SYNAPTA. 
Tentacula more than five, sometimes 12; rarely simple, 
mostly digitate; calcareous plates perforated, and having 
anchor-shaped spicula articulated to them. 
Genus, CHTRODOTA. 
Tentacula 12; digitate at the extremities; peduncle long, 
calcareous plates ‘ wheel-like,” but having no anchors or 
other spicula ; articulated. Whilst the species described may 
be'characterised thus: 
Synapta digitata—Having 12 tentacles and 4 fingers to 
each tentacle, with a small thumb. 
Anchors plain, with 3 or 5 serrations. 
Anchor plates oval and leaf-shaped, having a process or 
stalk at the end to which the anchor is articulated; disk 
perforated with 4 large simple holes, which are surrounded 
by smaller perforations sometimes ; anchor plate obcordate ; 
articular process has a slit like the eye of a needle. 
S. inherens.—Having 12 tentacles with 5 pinne on each 
ae and 1 terminal digit; 8 blow holes or trumpets on 
each. 
