184 SUMMARY OF CURRENT RESEARCHES RELATING TO 



of occurrence, and establishes the new genus Lessertia, which he dis- 

 tinguishes from the nearly allied Leptorhoptrum Kulcz and Tmeticus 

 Menge. 



New Marine Spider.* — Louis Fage describes Desidiopsis racovitzai 

 g. et sp. n., found by Racovitza among the calcareous algge on the 

 Mediterranean shore. It is related to Desis in the sub-family Cybceina?. 

 It lives in burrows of Lithodomus, in empty shells of Vermetus, or in 

 crevices, and its web varies with the situation. Numerous threads 

 across the mouth of the hole help to keep the water out. It can 

 remain for a long time under water, the abdomen surrounded by an 

 envelope of air ; it can creep about, but has to hold firmly else it would 

 rise to the surface ; unlike Argyroneta it cannot swim. It probably 

 lives on small Diptera and mites. 



Scottish Hydrachnids.f — W. Williamson discusses early papers by 

 Johnston (1848) which seem to be the earliest British records of 

 Hydrachnids. Johnston describes three species : Hydrachna cruenta 

 Mull. (Johnston) ~ = Diplodontus despiciens (Mull.)] ; Atax his- 

 trionicus ' = Limnesia histrionica (Herm.)], and Hydrachna naica 

 Johnston " = Hygrobates reticularis P. Krani., = Hygrobates na'icus 

 Johnston], 



Hydrachna. j — C. D. Soar discusses this genus, and gives a very 

 useful table for the preliminary identification of British species. He 

 recognises twenty-one of these, fourteen previously recorded, three new 

 to the British fauna, and four new to science. Many probably remain 

 to be discovered, for few districts in the British Isles have been system- 

 atically worked. 



f, Crustacea. 



Variation in Palsemonetes varians.§ — Arthur Brozek has made a 

 biometrical study of this Decapod from four localities — Lago de Castello, 

 Italy (fresh water) ; Montenegro, two lakes (fresh water) ; and Plymouth 

 (brackish water). Like previous workers on this subject, he devotes 

 special attention to the rostral teeth. 



Blood-forming Organs in Cumacea.|| — L. Bruntz has found in 

 Iphinoe tenella G-. 0. Sars, a pair of dorsal lymphoid organs forming 

 blood corpuscles. They lie in the anterior portion of the fifth thoracic 

 ring. Thus the Cumacea are no exception to the distribution of these 

 organs in higher Crustacea. Only in Leptostraca do they seem to 

 be absent. 



Abnormal Oviducts in Lobster. f — W. G. Ridewood describes a 

 specimen of Homarus vulgaris, which had a normal oviducal opening on 

 the right side, and two on the left — on the fifth leg (where the vas 

 deferens of the male normally opens) and on the fourth leg. The 



* Arch. Zool. Exper., ix. (1908) Notes et Revue No. 4 pp. lxxv-lxxxiv. (9 figs.). 



t Ann. Scot. Nat. Hist., Jan. 1909, pp. 27-30 {1 fig.). 



j Journ. Quekett Micr. Club, Nov. 1908, pp. 271-82, (1 pi.). 



§ S.B. k. Bohm. Ges., 1907 (published 1908) No. xvi. pp. 1-27 (1 pi.). 



|| Arch. Zool. Exper, ix. (1909) Notes et Revue, No. 4, pp. lxv.-ix. (2 figs.). 



f Ann. Nat. Hist., iii. (1909) pp. 1-7 (2 figs.). 



