194 PERCY SLADEN TRUST EXPEDITION 
other matters connected with the literature are mentioned in the writer’s paper in 
vol. xv. of these Transactions, 1912, p. 215. 
It is a pleasure to express my thanks for the generous help which I have 
received from several entomologists in dealing with these families of Coleoptera. Monsieur 
Charles Alluaud has very greatly assisted me by lending a number of specimens for 
purposes of comparison. I am specially indebted to Monsieur P. Lesne for his kindness 
in lending me valuable specimens from the Paris Museum, and for comparing specimens 
which I have sent to him with species in the Paris Collections. Monsieur A. d’Orchymont 
has examined a number of the Hydrophilide ; I am indebted to him for several deter- 
minations and for allowing me to make absolutely unrestricted use of his very full and 
accurate manuscript-notes 
receive certain minute forms among them. 
on them. Lastly I have to thank Mr George Lewis for 
determining certain of the Histeridze and for the gift of several valuable specimens. 
Hydrophilide. 
23 species, representing 12 genera, are here enumerated from the islands visited 
by the Expedition. Only 6 species had previously been recorded. Of the 17 additions, 
9 are described as new to science, and it has been necessary to erect 3 new genera to 
22 species are actually represented in the 
collection made by the Expedition : the remaining one (C@lostoma punctulatum) has been 
recorded as found by a previous collector. 
The distribution of the species, so far as known, is shown in the following table: 


Before the names of the species: 
| * indicates that the species is new to science, 
+ indicates that the species is recorded from 
these islands for the first time, but not 
new to science. 
Distribution among the islands 
visited by the Expedition 
Seychelles| Coetivy 
Group Island aallatoronra 
External Distribution 

* Hydrena mahensis............ | 
7 Berosus acutispina............ 
+ Berosus prolongatus ......... 
Berosus bergrothi ............ 
Volvulus stagnicola ......... | 
* Paracymus alluaudianus 
Helochares melanophthalmus 
Helochares melanophthalmus )| 
var. sechellensis {| 
8. Philydrus parvulus ......... 
9. 7 Philydrus abnormalis......... 
10. *Paromicrus carinatus......... 
11. *Paromicrus thomasseti ...... 
12. *Paromicrus atomus............ 
13. Dactylosternum insulare ... 
14. 7 Dactylosternum pygmeum 
15. fCclostoma rufitarse ......... 
16.  Celostoma punctulatum 
17. *Bourdonnaisia mahensis ... 
18. *Bourdonnaisia silhouette ... 
19. *Cercyon fructicola ............ 
20. +Cercyon laticollis ............ 
| 21, +Cereyon uniformis ............ 
Ri Sd Sty G9 GS = 
22, CROC Ds scasooocesecodoenac00 
23. *Paroosternum degayanum... 



Madagascar 
Madagascar 
Madagascar 
Trop. Africa 
Madagascar, Africa, Trop. Asia, S. Europe 
| Madagascar, Africa, India, ce. 
Madagascar, British E. Africa, Ceylon, [? Sumatra] 
All warmer regions of Old World 
Mauritius 
Madagascar, E. and 8. Africa 
Madagascar, Africa 
| Madagascar 
Ceylon, India 
Y 



