Note on a New Xiphosuran.—Beecheyr. 145 
FIGURE 1. Prestwichia randalli. The type specimen; one and one-half 
times natural size. Chemung group, Warren county, Pennsylvania, 
The proximal genal regions are marked by flattened areas, defined 
by a slight angulation of the contour. These areas evidently corre- 
spond to the concavities on the ventral side, adjacent to the space occu- 
pied by the attached basal joints of the gnathopodites. 
Abdomen and telson unknown, 
The type specimen, consisting of a cephalothorax minus the right 
cheek, has a length of about 20 mm. The width from the center of the 
glabella to the outer margin is 22 mm., making the entire width 44 mm. 
The glabellar cone has a width of nearly 7 mm. at the base and tapers 
to a width of 2.5 mm. at the apex. A fragment of a larger cephalo- 
thorax has a length of 24 mm. A third specimen shows the entire out- 
line of the cephalothorax, and has a width of 46 mm. 
On account of the meagerness of the material, not many 
features can be used for a comparison of this species with 
Protolimulus eriensis Williams. The most obvious differences 
consist in the absence of the long, stout, genal spines, and the 
proportionately wider cephalothorax. <A species of Belinurus 
(B. kiltorkensis Baily) has been described by Woodward* 
from the Upper Old Red Sandstone of Ireland, and this Is 
also quite distinct from the present form in having genal 
spines and a relatively longer cephalothorax. 
The lobation at the sides of the axis may be compared with 
that in the glabella of many trilobites, and may be likewise 
indicative of the number and arrangement of the paired ap- 
pendages beneath. The median node at the end of the conicaf 
axis probably denotes the position of the forcipulate antennz 
which were doubtless close together in front of the mouth, as 
in Limulus. The lateral or jaw lobes are five in number and 
of nearly the same dimensions, from which it may be inferred 
*A Monograph of the British Fossil Crustacea of the Order Merostomata, 
party, p.2838. Palaeontographical Society, 1878. 
