HERM^A. 33 



Alderia modesta, Loven. 



A. modesta, Allm. in Ann. N. H. 1st ser. xvii. p. 4 ; A. & H. Brit. Nud. 

 Moll. fam. 3, pi. 41. f. 1-5. 



Body ovate-oblong, subconvex, yellowish or greenish, gene- 

 rally more or less variegated and spotted with brownish grey: 

 head small, slightly notched in front, and produced at the sides 

 into obtuse lobes : branchial processes elliptic-oblong, obtuse, 

 coloured like the body, and arranged in 6 or 7 diagonal rows 

 on the sides of the back, increasing in size posteriorly : foot 

 large and broad, rounded in front and reflected upwards at the 

 sides. L. 0-5. 



Habitat : Gregarious on Confervee in shallow brackish water, 

 in a salt-marsh at Skibbereen, county Cork (Allman); Loughor 

 Marsh, near Swansea (Bate, Jeffreys, and Moggridge); in a 

 salt-marsh at Hylton Dene, Durham (G. S. Brady). [Escaut, 

 below Antwerp (Nyst, as A. scaldiana).^ 



This curious animal is almost amphibious, being only found 

 in very shallow brackish water in marshes, barely within the 

 reach of the tide, and occasionally crawling on the moist weed 

 beyond. It is a rare [or local] species, but generally plentiful 

 where it does occur. It was first met with in Sweden by 

 Professor Loven, who published it under the name of Stiliger 

 modestus in the Transactions of the Royal Swedish Academy ; 

 but he afterwards adopted the generic appellation here given 

 in his ' Index Molluscorum Scandinaviae/ 



Genus II. HERM^EA* Loven. 

 [PI. II. f. 1.] 



Body elongated, tapering posteriorly : tentacles 2, ear-shaped 

 or longitudinally folded : branchial processes linear-oblong, 

 tapering, placed along the sides of the back: vent antero-dorsal : 

 odontopho re with a single series of plates bearing a broad spine. 



1. HermtEA bi'fida, Montagu. 



Doris bifida. Mont, in Linn. Trans, xi. p. 198, pi. 14. f. 3. H. bifida, 

 A. & H. Brit. Nud. Moll. fam. 3, pi. 39. 



Body linear, very slender, tapering to a fine point behind, 



* [Mercurial or agile.] 



c5 



