508 Mr. J. N. Halbert on 
with the pharynx. The lateral processes stand out rather 
abruptly from the sides, slightly recurved at the inner angles. 
The pharynx is broad and strongly rounded at the sides; air- 
tubes about as long as the pharynx. 
The palps are rather long and slender, measuring about 
1:26 millim. in length. Second segment* with 4 or 5 
weakly feathered spines along the distal margin. Third with 
7 or 8 short stout spines on the distal corner, one or two of the 
innermost of these distinetly feathered. Fourth with about 
10 long spines towards the inner margin; six of these are 
arranged more or less in pairs. 
Locality. Collected by Mr. H. L. Orr in Lough Gullion, 
County Armagh, May 1901. 
Eylais Koenikei may be compared with the North-American 
species L. falcata, Koen. The bridge connecting the eye- 
plates is much longer and narrower in the Ivish species. 
Another difference is in the position of the hair-papille, 
which in falcata are situated on the inner corner of the eye- 
capsules, not on the bridge. In falcata also the pharynx is 
of a regular long oval shape, quite unlike that of #. Koenzkez. 
Eylais extendens (Miiller). 
1776. Miller, O. F., Zool. Dan. Prodr. p. 190. no. 2272. 
The species figured t by Piersig as the type of H. ex- 
tendens (Miiller) occurs in Ireland, although it is not by any 
means the commonest species found there. The eye-plate 
varies chiefly in the depth of the posterior emargination, also 
in the outline of the anterior margin, which may be quite 
straight, or with a marked indentation in the centre. 
Eylais symmetrica, sp. n. 
A large species, measuring about 4 millim. in length. 
The eye-plate (fig. 3) is very large and of a marked type 
of structure, rather resembling that of EZ. perincisa, Ribaga; 
greatest breadth across *51 millim., length of single capsule 
‘20 millim. Anterior margin of the bridge with an evenly 
rounded hump on each side of the middle line, divided by a 
sharply pointed rather deep indentation ; muscle-attachment 
large and circular, with or without a long chitinous process. 
Posterior emargination very deep, equalling two thirds the 
* Throughout these descriptions the spines clothing the inner surface 
of the palps are alone referred to, as in this respect the inner surface is 
always the most characteristic. 
t 1900, Deutschlands Hydrachniden, pl. xlviii. figs. 119 a-A. 
