ANNALES, XLII (1907). 268 



II. — Genus HAPLOPHTHALMUS Schôbl. 



There are tvvo European species of tins interesting genus botli of 

 which 1 hâve pleasure in recording below from Belgium. 



1. — Haplophthalmus Mengii Zaddo< h. 



ltea Mengii Zaddoch, Syn. Crust. Prussicorum prod 'romut Reffiomonti t p. 16, 

 1844 : Haplophthalmus elegans Schôbl, Sitz. der math, xattrw. A< ad. Wiss. 

 Wien, XL (1860), p. 449 : Haplophthalmus Mengii BUDDB-LuND, Cr\ 

 Isopoda Terrestria, p. 250, 1885; G. 0. Sars, Crustacea ofNonoay^ II. p. l< 

 pi. LXXIV, fig. 1, 1898; Webb and Sillem. British Woodlice, p. 26, 

 pi. VII, 1906. 



I have taken tins rare and very distinct species in many British 

 localities and at Grùne near Letmathe (Westphalia), Germany. 



Belgium. — A single example with Trichoniscus pijgmœus at 

 Antwerp, November, 1907. 



2. — Haplophthalmus danicus Budde-Luxd 



Haplophthalmus elegans Budde-Luxd (not Schôbl), Natukhistorisk. Tidsskrift, 

 pt. 3, VII, p. 228, 1870 : Haplophthalmus danicus Budde-Luxd, Crustacea 

 Isopoda Terrestria, p. 9, 1879 : Haplophthalmus Mengii Weber (not Zad- 

 doch), Tijdschr. der Nederi.axdsche Dierk. Vereex., V, p. 192, pi. V. 

 figs. 7-9, 18 : Haplophthalmus danicus G. O. Sars, Crustacea of Norway , II, 

 p. 168, pi. LXXIV, fig. 2, 1898; Wemb and Sillbm, British Woodlice, p 

 pi. VIII, 1906. , 



Also of wide European distribution and often found in numbers. 

 Thèse two forms are much slower in their movements than most 

 species of Trichoniscus, and owing to its coloration (in a sensé pro- 

 tective) in conjunction with its sluggish movements //. Mengii Zadd., 

 is really very difficult to detect. H. danicus is often found frequent- 

 ing moderately cool greenhouses and I have récent ly discovered 

 living with it a long, linear, slow-moving species of Trichoniscus 

 which curiously simulâtes tins species ('). 



Belgium. — A single example amongst moist earth al pool of 

 tree, Botanical Gardens, Brussels, November, 1907. 



(') This is the Trich linearis, bd. nov., shortlj to b»' deecribed bj 



Patience. 



