Water-beetles. 5 



15. Yola costipennis, Fairm. A variety in which the dark 

 marks are very extensive. The species, though rare, has been 

 recorded from Madagascar and Senegal. 



Three specimens on waterplants, White Nile, Gebel Ahmed 

 Agha. 



B. Hydrophilidae. 



16. Sternolophus solieri Casteln. This common species 

 appears to be abundant in the White Nile. 



Twelve specimens from Cairo; eleven from the White Nile, 

 Shellal Gebelein; two from the White Nile, Gebel Ahmed Agha. 



17. Paracymus sp. A single specimen of a minute Para- 

 cymus was met with at Gebel Ahmed Agha in March. 



18. Berosus sp. Two specimens in bad condition closely 

 allied to B. decrescens Walk, from Ceylon, but rather darker in 

 colour and with denser punctuation on the elytra. 



On waterplants, White Nile, Gebel Ahmed Agha. 



19. Volvulus niloticus n. sp. Anguste orsalis, niger, supra 

 laete aeneus, dense subtiliter punctatus ; antennis palpisque flavis,. 

 his apice angustissime nigricante, illis clava fuscescente, pedibus 

 piceis, anterioribus sordide rufis; elytris subtiliter punctato-striatis. 

 Long, (capite deflexo) 4. 1 /* — 5 mm. 



This is distinguished from all the other species by the 

 more numerous punctures of the upper surface and the very 

 fine striation of the elytra; the striae are quite indistinct on 

 the portion near the scutellum; at the sides the striae are distinct. 

 The spine formed by the compression and plication of the hind 

 part of the last ventral plate is very distinct, and the armature 

 of denticles on each side of it is quite evident. The distinction 

 of the sexes is very slight, though the cupules on the under- 

 surface of the front tarsi in the male can be seen without 

 difficulty. 



Gebelein, February, one specimen. Gebel Ahmed Agha. 

 March. Nine specimens. 



20. Volvulus jaegerskioeldi n. sp. Anguste ovalis, niger, supra 

 aeneus, crebre punctatus; antennis basi testacea, palpis pedibus- 



