Trish Species of Wylais. 513 
rather weakly developed, with from 12 to 14 rather slender 
feathered spines ; fourth with very numerous spines grouped 
regularly along the sinuate inner margin. 
Fig. 8. 
Localities. Fish Pond near Gorey, and at Enniscorthy, 
County Wexford ; also in the Portmarnock Brickfields, near 
Dublin. 
Eylais infundibulifera, Koenike. 
1897. Abh. Ver. Bremen, Bd. xiv. pp. 284, 295, figs. 3, 4. 
This is probably the commonest and most generally distri- 
buted species in Ireland. I have taken it at Lough Neagh ; 
in the River Corrib, Galway ; the Blackwater, Co. Cork ; 
Lough Gur, Co. Limerick; and at various localities near 
Dublin. 
The eye-plate of this species is subject to great variation. 
I have seen Dr. Koenike’s type specimens, and, as he has 
himself clearly stated, there can be no doubt that this species 
is the same as LE. bifurca, Piersig. Dr. Koenike’s specimens 
agree excellently with the description and figures of the last- 
named species (Deutschl. Hydrach. pl. xli. figs. 120 a, 0). 
The following is a description of an Lylads which, although 
it differs very strikingly from the type form of ¢nfundibu- 
lifera, Koenike, should, I think, be referred to a variety of 
that species. It may be called 
stagnalis, var. Ne 
The eye-plate (fig. 9) is very large, measuring about 
*50 millim. across, length of single capsule °30 millim. 
Anterior margin produced at centre in a narrow irregularly 
pointed process, the apex of which serves for a muscle- 
attachment; on each side of this the bridge is slightly undu- 
late ; posterior emargination broad, deep, and evenly rounded, 
leaving a chitinous bridge, varying from ‘05 to ‘10 millim. in 
