338 MR. E. SHELFORI> ON A COLLECTION OF 



EctoUas lap2?onicus than to any other recent member of the genus, and it is 

 tempting to suppose that the modern species is a direct descendant ol^ one 

 of the amber-enclosed forms. If this is so, we may perhaps continue our 

 speculations imd assume that whilst the onset of more rigorous conditions of 

 climate eventually drove southwards the great bulk of the cockroaches of the 

 amber fauna, two species of Ectobius held their ground and one of these has 

 persisted with subsequent small modifications of structure until the present 

 day. That the climate of N. Europe during the Glacial Epoch was of such 

 severity that animal life was rendered impossible is, in the light of modern 

 researches, extremely unlikely ■^, and there is nothing inherently improbable 

 in the view that an insect could persist in one area from Oligocene to recent 

 times with only slight changes in structure. 



The unique specimen which I refer to the genus Holocompsa is most nearly 

 allied to H. minutissima, de Geer, originally described from Surinam ; but 

 this and the two Ectohii are the only species which I can compare with 

 any confidence with modern species, and in view of the almost world-wide 

 distribution of the genera represented in the amber-deposits by adult forms 

 it would be most hazardous to attempt to compare this fauna with any 

 particular tropical fauna of to-day. Yet if I am right in determining a 

 single damaged moult as belonging to a species of Nyctibora, we have, in 

 conjunction with the undoubted affinities of the single species of Holocompsa^ 

 slight indications of a remote connection between the modern Neotropical 

 fauna and the amber fauna, for the entire subfamily JSyctiborince is now 

 confined to the Neotropical region of the world. 



A few remarks may be made on the condition of the specimens wdiich I 

 have handled. The great majority are in a most admirable state of preser- 

 vation and with a high-power simple lens it is generally possible to make out 

 nearly all the details of their structure without great difficulty. When I 

 reflect on the enormous antiquity of these absolutely perfect specimens 

 I cannot refrain from expressing a hope that some method will shortly be 

 devised for enshrining in a similar way in balsam or other resin the type- 

 specimens of recent species of insects. As the science of entomology 

 advances the importance of the type-specimen ever increases ; unfortunately 

 the ravages of mites, Anthreni, dust, mould, and careless students are often 

 disastrous, and we bemoan to-day the irreparable loss of specimens that would 

 afford valuable clues to hopeless tangles of synonymy. It is sad, but none 

 the less true, that it is possible to make out more of the external anatomy of 

 the Olio'ocene Ectobius balticus from an examination of specimens many 

 thousands of years old, than of the recent Ectobius lapponicns from an 

 examination of Linnteus's type, the shattered wreck of which is preserved 

 in the cabinets of this Society. 



* Cf. Scharft : ' The History of the Europeiin Faima; 1899. 



