SCOTT—COLEOPTERA; HYDROPHILIDA, HISTERIDA 195 
It is seen that no Hydrophilidze were collected in the Chagos, Amirantes, Farquhar, 
or Cargados Carajos groups of coral-islands, and none have ever to my knowledge been 
recorded from those groups. 
The table shows that 18 species were found in the Seychelles: 15 of these were 
found only in that archipelago (and, in the case of two of them, in the outlying 
coral-island of Coetivy, close to the South); 3 species were found also in Aldabra. 
9 species in all were found in Aldabra, that is the three (all widely distributed species) 
which occur also in the Seychelles, and six others. In discussing affinities it will be 
best to consider the Seychelles and Aldabra separately. 
Seychelles. Of the 18 species, 13 are terrestrial and 5 are aquatic. Among the 
terrestrial forms there is almost certainly an endemic element in the fauna, consisting 
of the completely wingless new genus Bowrdonnaisia, represented by two distinct 
species each confined to a single island: the extreme restriction of their habitat to 
the very summits of the highest peaks, in the heart of the endemic forests, is dealt 
with on p. 215. In affinities this genus appears to be isolated. 
The second new genus, Paromicrus, is fully winged, and represented by three 
minute species, not confined to single islands nor so restricted in habitat as Bowrdon- 
nosia, but still almost entirely confined to the endemic forests, where they are 
amongst the most abundant beetles under the bark of decaying wood (see p. 207). 
This genus is allied to the Hawaiian Omicrus: at first I thought it was endemic to 
the Seychelles, but M. d’Orchymont has informed me (in /itt.) that he has two other 
species, one from Engano, a small island south-west of Sumatra, the other from the 
Abor country (Assam), Neither of these is identical with any of the Seychelles species, 
specimens of all of which were submitted to M. d’Orchymont: so the Seychelles species 
may perhaps be confined to those islands, though the genus is not. 
The third new genus, Paroosternwm (also fully winged), is represented by only two 
specimens: it is allied to a genus known from Central America and Japan. Such 
affinities may seem remarkable, but until Hydrophilide so minute as these have been 
more thoroughly collected throughout the world, it would be unwise to attach too 
much weight to them. 
Among the remaining land-inhabiting Hydrophilide it is doubtful whether there 
is any endemic element at all. Dactylosternwm insulare (found also in Aldabra) is 
very wide-spread: Dactylosternum pygmeum is known from Mauritius: Celostoma 
punctulatum is wide-spread African and Madagascan: Cercyon fructicola may perhaps 
be allied to a form known from Mauritius : Cercyon laticollis is known from Madagascar ; 
Cercyon uniformis from Ceylon and India. These species are all found in rotting fruit. 
—very often in the fruit of imported trees—at various elevations (see locality-lists), 
and, with the possible exception of Cercyon fructicola, are probably immigrant or 
imported species. 
Turning now to the aquatic forms: the writer has several times mentioned* that 
the very numerous mountain-streams of the Seychelles have only a small aquatic insect- 
* Trans. Linn. Soc. London, Ser. 2, Zool., xiv. 1910, p. 28: ibid. xv. 1912, pp. 242, 258. 
