HH. Woodward—Descriptions of New Paleozoic Crustacea. 197 
for November, 1863; and I now propose to point out the cha- 
racters of Stylonurus. 
Since Mr. Page figured Stylonurus Powriei in 1856,* then the 
one only species known, much better specimens have been found 
by Mr. James Powrie, of Reswallie, in Forfarshire, and Mr. 
Robert Slimon, of Lesmahagow, in Lanarkshire. A specimen 
of a new species of this genus, from the last-named locality, 
furnishes us with such interesting details that I subjoin a 
detailed description. 
1. StyLonuRvus Loeani. Sp. nov. Pl. X. fig. 1. 
Only one specimen, from Lanarkshire (Logan- Water, near 
Lesmahagow), is known of this genus, the ¢ntaglio half of which 
is in the Museum of Practical Geology, Jermyn Street, and the 
relievo half in the collection of Mr. James Powrie, of Reswallie. 
It is from the latter half that our figure (Plate X. fig. 1) is 
taken. 
The specimen exhibits the carapace and the body-rings, as far as 
the 10th segment, united, and one of the long slender eight-jointed 
swimming-feet in s7té on the right side; whilst on the left are seen 
the bases and portions of two more long appendages. Lying upon 
the slab, in various positions around the head, are four spiny 
eight-jointed palpi, or foot-jaws, one of which still retains its at- 
tachment tc the carapace, although twisted and bent from its 
natural position. 
Upon referring to the figure of Stylonurus Powriei in Page’s 
‘ Advanced Text-book’ (8rd edit., p. 190, fig. 1), it will be seen that 
it has ¢wo pairs of long slender swimming-feet upon either side of 
the head. In the specimen here figured, from Logan-Water, there is 
also evidence of a second pair of long limbs, making, with the spiny 
palpi, four pairs of appendages ; the fifth pair (absent), being the 
antenne, were probably much smaller, as in Kurypterus (see GHOL. 
Maa., Pl. V. figs. 7-9). The form of the carapace in Stylonurus is 
well marked, and very different from any other genus in this sin- 
gular family. 
In the Logan-Water shales, although the finest and most delicate 
markings are often preserved, yet the specimens are so compressed 
as to give scarcely any idea of their original contour, except by 
comparison with those from the Old Red Sandstone of Forfarshire 
and elsewhere. ‘The eyes are situated upon the surface of the cara- 
pace, somewhat near the anterior angles. ‘They were reniform, and 
raised upon round prominent bosses; but these are now squeezed 
flat to the surface of the head. 
The carapace is quadrate, with the anterior angles rounded; the 
sides present a slightly waving outline, contracting towards the 
posterior angles. ‘The margin is double, having an inner ridge 
which circumvents the sides and front, and terminates in a rounded 
* See Page’s ‘ Advanced Text-book of Geology.’ 
