80 Scientific Proceedings, Royal Dublin Society. 
descends to a considerable distance on the ventral surface; the 
broad pale yellow brain descends to, and apparently rests upon 
the forepart of the mastax, and at its extremity are three or four 
dark grey round cells, upon which is seated anteriorly a lovely 
rose-red globate eye. A pair of small round auricles are occasion- 
ally everted almost on a line with the frontal margin. The 
enormous forcipate trophi spring from the middle of the body and 
are peculiarly weak and slender in proportion to their length. 
The stomach is long and narrow, reaching close to the foot; no 
other organs were visible. ‘The foot, composed of one or two (?) 
joints is conspicuous and rather flat; the toes, a trifle longer than 
the foot, are slender, pointed, slightly decurved, and habitually 
adpressed. 
Its manners are slow and methodical; it adhered firmly by 
the toes to a certain spot, and from thence twisted about in all 
directions, working the cilia vigorously for over an hour; some- 
times. it lifted the head up, and revolved around, everting the 
small auricles, then again bent downward. I noticed that the 
trophi were hardly ever brought into use, and seemed very feeble. 
In the position of the dise this species closely resembles JV. 
saccigera, but the shape and size of the head, the conspicuous foot, 
and slender tapered and pointed toes, are widely different. 
Length 4, of an inch. 
Habitat—Amongst Callitrichia verna, from a pond, Oo. 
Wexford. 
Notommata gigantea, sp. nov. 
[Pl. VII. fig. 1.] 
Sp. Ch.—Body cylindric, stout; head very small, truncate ; 
no auricles; brain small; eye minute; trophi very small, forci- 
pate ; foot saccate; toes minute; stomach enormous; ovary very 
large; contractile vesicle small, globate; tail conspicuous. 
This is one of the largest of the genus I have yet seen. Its 
form is a stout cylinder, narrowed at either end. The integu- 
ment, in fully matured examples, of great transparency, and puffed 
out from the viscera to a considerable distance, thus affording an 
excellent view of the internal organs, the minutest details of which 
can be studied with ease. The head is remarkably small, the dise 
