SCIENTIFIC SUMMARY. 
425 
three specimens of the 1 lash ’ or ‘ glass-cord ’ in situ, and fragments of the 
fluked ends of the anchoring spicules of the same lash, probably, but 
separate” thus furnishing all the skeleton-spicules that a hyalonematous 
sponge could present. The flesh-spicules, from their minuteness, could 
hardly have been preserved. The author is of opinion that probably the 
fossils described under the name of Acanthaspongia , McCoy, and Proto- 
spongia, Salter, are also remains of sponges of the same group as the 
above. 
A new British Coral. — Professor Nicholson and Mr. R. Etheridge, Jun., 
have described (“Ann. Mag. Nat. Hist.,” Sept. 1877) a new species of 
tabulate coral, which they refer to Professor Dana’s genus Tetradimn,” the 
distinctive characters and affinities of which they discuss at considerable 
length. They come to the conclusion that Tetradium is most nearly related 
to Holy sites, but with some affinities to Chcetetes , thus forming a sort of con- 
necting link between the two families of tabulate corals, the Halysitidce and 
Chcetetidce. They notice two species of the genus : — the Tetradium minus 
of Safford, from the Silurians of the United States and Canada (Cincinnati 
and Hudson River Groups), and T. Peachii, a new species found in pebbles 
of Silurian limestone, contained in the Old Red conglomerates of Habbies 
How, in the Pentland Hills, near Edinburgh. 
A Silurian Annelid. — Worm-tracks have been long known as almost the 
only indications of the existence of animals in certain very ancient rocks, 
but in these nothing more than the tracks have been detected, whilst in 
some fossiliferous deposits, the only traces of annelids have been of a similar 
nature. Air. G. B. Grinnell now describes (“ Silliman’s Journal/’ Sept. 1877), 
some remains, apparently of Annelids, obtained by Air. A. G. Wetherby, from 
Lower Silurian rocks near Cincinnati. He regards the bodies fossilized as 
probably the jaws of a worm allied to the existing genus Nereis. He de- 
scribes the largest and most perfect jaw, which is rather more than a fifth of 
an inch long, as of a dark brown colour, hollow from the base throughout 
the greater part of its length, and having numerous denticulations (eight are 
preserved in the specimen) along its side. The anterior tooth is the largest 
and slightly twisted outwards j the teeth towards the base are deficient. 
He also notices another form, which bears eighteen teeth, of which the 
anterior is long and stout, the five following very small, and the remainder 
sharp and strong. This fossil is only half the length of the other, and the 
author seems inclined to identify it with one of the setae of a nereiform worm. 
A new Triassic Lizard. — Professor Oscar Fraas describes and figures 
(“Wiirttemb. naturw. Jahreshefte, xxxiii. Heft. 3, 1877”) a most extra- 
ordinary group of fossil reptiles, obtained from a sandstone quarry in the 
Aliddle Keuper, near Heslach. No fewer than twenty-four individuals of 
the same species were found in a slab of sandstone having a surface of 
about two square metres j the animals were beautifully preserved, and in 
some cases their attitudes are almost life-like, all the hard parts, including 
the bony dermal scutes, being there in their natural position. The effect of 
the group is increased by the fact that all these bony parts have become con- 
verted into vivianite, the blue tint of which contrasts wonderfully with the 
greyish colour of the stone. Professor Fraas describes this animal in great 
detail, and refers especially to certain bird-like characters presented by the 
NEW SERIES, YOL. I. — NO. IY. FF 
