68 THE ZOOLOGIST. 
ON THE EVOLUTION OF DINARDA, A GENUS OF 
COLEOPTERA. 
By Erico Wasmann, S.J.* 
(Translated by Horace Donisthorpe.) 
As an instance of recent species building,....... I 
brought forward, in 1901,+ the genus Dinarda, in the Brachy- 
elytra (Staphylinide). It can be shown that our North and 
Central European two-coloured (red and black) forms of Dinarda, 
which are adapted to different species or races of the genus 
Formica, stand in different stages of species building. ‘Two of 
these—Dinarda dentata (with F’. sanguinea) and D. mdrkelt (with 
F’. rufa)—have already become throughout their area of distri- 
bution such constant forms that they have been hitherto not in- 
correctly treated as species. ‘Two other nearly related forms, on 
the other hand—D. hagensi (with F’. exsecta) and D. pygmea 
(with F’. rufibarbis, and especially with the var. fusco-rufibarbis) 
—are still considered to be in the process of adaptation to their 
ant-hosts; in some parts of the area of distribution of the latter 
they have already become well-detined forms; in other regions 
they still show numerous transitions towards D. dentata; finally, 
in others, no adaptation of Dinarda to F. exsecta and rufibarbis 
has yet taken place. We have also before us in these two forms 
of Dinarda, which gradually approach in the path of variety and 
race-building, every stage of species building which has already 
been reached by Dinarda dentata and marke. My previous 
observations have strengthened these ideas in essentials, and at 
the same time have also afforded some further points of con- 
firmation relative to external factors, which imply these processes 
of differentiation with regard to adaptation.t 
* Sonderabdruck aus der Festschrift fiir J. Rosenthal., Leipzig, 1906. 
+ ‘Gibt es tatsichlich Arten, die heute noch in der Stammesentwickelung 
begriffen sind?” (Biol, Centralbl. xxi. nr. 22, u. 23). 
| See my book also on this, ‘ Die moderne Biologie und die Entwicke- 
ungstheorie ’ (Freiburg, i. B. 1904), pp. 214-215. 
