2 Transactions of the Society. 



examinations of this form, which, I am now convinced, has specific value. 

 The crescent behind is glassy clear throughout, continuous with the body, 

 not articulated ; its form is that of the new moon when first visible. 

 Cf. Balatro clavus Clap. (Plate I. fig. 1.) 



2. Diglena (?) siljjlia. Body sub-cylindric, stouter at the head, 

 abruptly lessened behind ; brain saccate, long, opaque at the end ; toes 

 minute, conical. Length 1/100 in. Lacustrine. 



The whole animal is very soft and plump, not wrinkled, even in 

 retraction. A well-marked, soft, decurved proboscis is on the front : no 

 eye is visible. The sudden attenuation of the body to a slender cylinder, 

 one-fourth of the whole length, is remarkable ; this terminates in two or 

 three soft lobes, below which are two very minute toes, with no appre- 

 ciable foot intervening; for the rectum can be traced to a cloaca, just 

 above the toes. Fuller examination is needed : I have seen but a single 

 examjile, sent from the middle of Ireland ; and the trophi were not satis- 

 factorily defined. (Fig. 2.) Cf. Notommata forcipata, lat. aspect. 



3. Notommata ovidum. Very small ; body globose, plump ; dorsum 

 gibbous ; venter flat : brain clear ; eye wanting : foot short ; toes rather 

 long, acute, decurved. Length 1/370 in. Lacustrine. 



This attractive little form has so much resemblance to N. lacinulata, 

 that I had doubted whether it is not a var. of that species. There are, 

 however, divergences, important, if minute. It is very much rounder in 

 all aspects ; the toes are longer, uniformly diminishing to acute points, 

 and decidedly decurved : no trace of eye could be discerned. It swims 

 rapidly, but evenly ; does not spring, and does not ttvitch ; — both which 

 actions are so characteristic of lacinulata. Auricles (?) are occasionally 

 pushed out. The front projects in a tubercle, halfway between which 

 and the auricle on each side is a stiff seta. I have examined three 

 specimens, two from Woolston, and one from Dundee. (Fig. 3.) 



4. Fureularia melandociis. Body swollen, obtusely narrowed in 

 front, tapering behind: brain saccate, opaque at the extremity: foot 

 large; toes conical, each terminating in a soft, slender point, much 

 produced. Length 1/130 in. Lacustrine. 



Of excessively versatile outline, rapidly lengthening and shortening 

 every instant. The front is apparently hard, with a sharp edge, below 

 •which is a broad, sub-prone, ciliate face. An ample brain-sac, — its 

 terminal portion filled with chalky deposit, usually intensely black by 

 transmitted light, but in some examples much diluted, — looks like a 

 bottle of ink swaying to and fro in the animal's contortions. The 

 prolonged finger-like tips of the toes (c) have a strong adhesive power, 

 dependent on a pair of great mucus-glands. A minute frontal eye is not 

 quite certain. Several examples have occurred in water from Woolston. 

 (Fig. 4.) 



5. Mastigocerca hicristata. Two equal sub-parallel carinae, running 

 nearly the whole length of the dorsum. Length 1/50 in., of which the 

 toe is nearly half. Lacustrine. 



Discovered near Dundee, by Mr. Hood, who sent me from time to 

 time many examples. It has a general likeness to ill. carinata, but 

 is much larger. 'Jhe double carina confirms the conjecture that the 

 asymmetry of that and other species is due to unequal development. 



