528 DAVID BRYCE ON TWO NEW SPECIES OF PHILODINA. 



various Scottish localities, including Loch Yennachar and Ben 

 Nevis. 



In confinement it is unusually hardy, and will live for months 

 in a fraction of a drop of water in a suitable cell. Tiike a few 

 other Bdelloid species, it is, under such circumstances, subject 

 at times to what must be looked upon as a pathological condition 

 of the gastric glands. These organs usually include in their 

 substance a small number of minute, clear spaces or vacuoles. 

 In this abnormal or diseased condition one (or more) of the 

 glands has some of the vacuoles so greatly enlarged that the 

 whole gland is like one large, clear vesicle, and in some cases is 

 swollen much beyond its customary size. Strange to say, this 

 condition of the glands does not appear to seriously affect the 

 health of the individuals attacked, or, at all events, to lead to 

 their rapid decease. When the disease shows itself, it generally 

 affects most of the individuals in the cell. 



Where P. nemoralis occurs, it is usually in fair numbers, and 

 it is certainly a widely distributed species, not uncommon in 

 its own group of habitats, but easily overlooked. 



Philodina rugosa, n. sp. 



Sp. Ch. — Small, rather stout. Skin of trunk shagreened ; 

 skin-folds prominent ; ridges roughened, transversely wrinkled, or 

 minutely sinuate. Rami 18 ju, long ; formula 3/3. Spurs short, 

 moderately slender ; bases separated by rather wide interstice. 

 Eyes small and round, 



I have much pleasure in giving to this species the name sug- 

 gested for it by Forstmeister L. Bilfinger, who gave me in 1894 

 some particulars of the form now described as the type. Two 

 years later I found a couple of specimens in moss collected in 

 Spitsbergen by Dr. J. W. Gregory on the occasion of Sir Martin 

 Conway's expedition to that island. W^ith the exception that they 

 were smaller, these specimens agreed well with the particulars 

 of those found by my correspondent near Stuttgart. 



The minutely sinuous and prominent ridges of the skin-folds of 

 the trunk give this form a very distinctive appearance. The 

 skin is somewhat opaque and of a greyish-brown colour. 

 The body is seldom seen extended, as the animal is extremely 



