Mr. G. J. Arrow on the Genus Rhysodes. 83 
organism was not accompanied by any figure. By referring 
to my description of this foraminifer from Funafuti*, it will be 
seen that it plays a very i1mportant part in the formation and 
consolidation of reef-rocks, and under certain conditions forms 
calcareous nodules as large as or larger than a pigeon’s egg by 
continuous laminar erowth. The young form of these extra- 
ordinary developments, however, resembles the Polytrema 
planum of Carter. My object in writing this note, therefore, 
is to withdraw the name ¢nvolva in favour of P. plinum. 
The various forms of Po/ytrema are not alone in making 
encrusting growths and nodules, tor other well-known ad- 
herent foraminifera, such as Gypsina and Carpenteria, encrust 
and enclose organic particles until they produce more or less 
spheroidal and elliptical nodules of considerable size; and 
these I hope to deal with shortly. 
XIV.—Remarks upon the Genus Rhysodes, with Descriptions 
of some new Oriental Species. By GILBERT J. ARROW. 
THE small Coleopterous family Rhysodide, the known species 
of which are fast becoming numerous, has been separated into 
various genera according to slight characters, many of which 
will probably be found insafficient as new formsoccur. They 
will, however, serve for present purposes, if some agreement 
can be arrived at as to their relative value. ‘The confusion 
arising from the want of such agreement was largely dispelled 
by Mr. George Lewis, who published in 1888 a list of the 
known species. His views, however, have not been entirely 
adopted abroad, while the adoption of his genus Lpiglymmius 
and another (Rhysodiastes) since proposed by Fairmaire 
necessitate, In my opinion, the formation of several more for 
species exhibiting equally good differential characters. 
Since commencing this paper I have learnt that M. Grouvelle 
contemplates the publication of a monograph on the family ; 
and since he has more complete materials than myselt, I have 
reduced my original intention to that of a partial review of 
the genus Lhysodes alone. I shall accordingly leave generic 
questions entirely to that entomologist, aud in the list of 
species which follows I include all the forms known to me 
which are distinguished by the possession of wings and the 
external conformation which accompanies that condition. 
* Journ. Linn. Soc. Lond., Zool. vol. xxviii. (1900) pp. 1 and 17, pl. ii. 
fig. 3, and text-fig. 2. 
6* 
