Miscellaneous. A 75 



one end of each being thus supported, the other forming a second 

 or onter coat or surface. One peculiarity, however, of their ar- 

 raiigement has suggested the specific name now given. In most 

 other species the length of the foraminal tube is fixed, or approxi- 

 mately indicated, by the thickness of the spiculiferous coat, which 

 closes up around and against it. In this, however, on account of 

 the unusual length of the spicules and their necessary radial direc- 

 tion, a space is left about the foramen, in the centre of which the 

 tubule appears as an elongated cone, the whole having the appear- 

 ance of a volcanic crater. In mounted specimens, probably as a 

 result of violence in making sections of the statoblasts, these spicules 

 frequently deviate from a direct radial position and cross each other's 

 lines in a curious manner. This sponge has also been found in the 

 Schuylkill river and in some of its smaller branches. 



Hcteromeiienui Byderii. 



This beautiful green sponge has, as yet, only been foimd in a 

 branch of Cobb's Creek, a small stream whose waters reach the 

 Delaware river, below Philadelphia. It occupied the upper surface 

 of large stones in the bed of the stream, some of the patches being 

 4 or 5 inches in diameter and about one fourth of an inch thick. 

 The surface is somewhat irregular, occasionally rising into rounded 

 lobes. The efferent canals are deeply channelled in the upper 

 surface of the sponge, live or six sometimes converging to a common 

 orifice. 



The skeleton-spicules are stout, cylindrical, slightly ctirved, gradu- 

 ally sharp-pointed, conspicuotisly spined, excepting at the extremities ; 

 spines conical, shar])-pointed, when largest often curving forward 

 or towards the adjacent ends of the spicules. As is generally the 

 case with spined skeleton-spicules, they are but slightly fasciculated — 

 being mostly arranged in a simple series, single sinculos meeting or 

 diverging from other spicules, thus forming a delicate network, 

 supporting the sponge-flesh. "With these are mingled a fe^ more 

 slender smooth spicules, which may be immature, or the true dermal 

 spicules of the sponge. 



The statospheres are numerous, rather small, surrounded first by 

 a series of birotulates, short, stout, the rotula) about equal in diameter 

 to the length of the shaft. The shafts are cylindrical or somewhat 

 wider towards the rotules, having frequently one or more long- 

 spines near the centre. Margins of the rotulte marked with an 

 infinity of shallow cuts not amounting to notches. 



The second series of birotulates, which, more than in either of the 

 other species of this genus, marks this as a deviation from the 

 familiar Meyenia ty|ie, are very different from the first. They are 

 nearly double the length of the former, much fewer in number, 

 rather regularly interspersed among them; the rotules are repre- 

 sented by six, eight, or more short recurved hooks at each end of 

 the shaft, which is cylindrical and studded with numerous spines 

 eqttal in length to the hooked rays of the rotuke, and curving, like 

 them, from the extremities. This species is respectfully dedicated 



