204 ROYAL SOCIETY OF CANADA. 



viiys, is about 0131 min. with ii brea<lth at the thickest part of about 

 0009 mm. The rays are slender and obtusely pointed, (Plate III., figs. 

 5, 5rt). 



The quadriradiates are few in number and occur in the gastral sur- 

 filées of the tubes. The fourth or apical ra}' is more slender and not so 

 long as the facial rays and is slightly curved at its extremity ; the facial 

 rays are similar in furm to the rays of the triradiates. An average sized 

 quadriradiate gave the following measurements : length of basal ray 

 0-124 mm., greatest thickness 0009 mm. ; length of lateral rays 0*104 mm. 

 (Plate III., hg. 56). A few small quadriradiates, which are probable- 

 young forms, also occur ; their rays are short, stout, acutely pointed and 

 about 0032 mm. in length with a thickness at the base of 0006 mm. 

 (Plate III., figs. 5c, 5d).^ 



Locality. — Orphan Bank, otf the entrance to the Baie des Chaleurs, 

 one specimen,' in alcohol, J. F. Whiteaves. 1873. 



Bistributim. — Gulf of vSt. Lawrence (J. F. Whiteaves) ; northeast 

 coast of the United States (Verrill). 



Sycon protectum. (Sp. nov.) 



(Plate III., figs. 6, 6((—g.) 



Sponge small, represented by a single specimen, egg-shaped, attached 

 b}' its broadly rounded base and with a large osculum at the upper end 

 surmounted by a fringe of long, delicate spicules ; total height 9 mm., 

 greatest breadth 3'75 mm. ; length of oscular fringe 4 mm. Colour in 

 spirit a very pale yellowish-gray ; the oscular fringe is of a glistening 

 white. Texture firm. >S'(//'/V/'e even, hispid. Oscw///w( circular r5 mm, 

 Avide. 



The wall of the S])onge, 5 mm. thick, inclo.ses a lai'ge central cavity 

 and is traversed by radial tubes about 0095 mm. wide. 



Skeleton. — There is a regular disposition of triradiate spicules in the 

 intervals between tlie radial tubes. An examination of the dermal surface 

 reveals the openings of the radial tubes, about 0'131 mm. apart from 

 centre to centre, arranged in regular rows ; between the openings oxeote 

 spicules deeply embedded in the parenchyma project beyond the outer 

 surface. Tlie spicides of the dermal skeleton are of a peculiar shape ; 

 they are triradiate. with the basal ray bent at mid-length at right angles 

 to the plane in which the lateral rajs lie ; they are arranged round the 

 dermal openings of the radial tubes, about twelve to each opening, so 

 that the bent basal rays are directed toward each other over the openings 

 of the tubes (Plate III., fig. 6^). The gastral skeleton is made up of 

 quadriradiate spicules whose apical rays i^roject beyond the gastral snr- 



' Identified by Prof, Verrill with the type of the species from the coast of Maine. 



