]•]{] ME. R. SHELFORD ON A COLLECTION OF 



On a Collection oi Blattid.e preserved in Amber, from Prussia. 

 By H. Shelford, M.A., F.L.S. 



(Platks 47 & 48.) 



[Read 16tli December, 1909.] 



In 1907 i)r. K. Klebs, of Konigsberg-i.-Pr., sent to me for study the major 

 part of his fine collection of Blattidse enclosed in amber, and this spring I 

 received from him the remainder. As practically nothing has been written 

 on the Blattidpe of the amber-deposits since the appearance of the great 

 memoir " Die im Bernstein befindlichen Hemipteren iind Orthopteren der 

 Vorwelt " * by Germar and Berendt in 1856, and as only 5 species of 

 Blattidfe were described in that work, it is not surprising that a study 

 of Dr. Klebs's large collection of these insects enables me to add con- 

 siderably to our knowledge of the fauna that flourished in the Oligocene 

 forests of East Prussia. I am greatly indebted to my kind correspondent 

 for the opportunity he has afforded me of examining a collection unequalled 

 in interest and wealth of material. 



All the specimens come from the well-known amber-deposits in the Baltic 

 provinces of East Prussia ; the deposits are of Lower Oligocene age and 

 correspond to the Headon beds in the Isle of Wight. As has long been 

 recognised, the insect-fauna of the amber-deposits differs in no very striking- 

 features from a characteristic tropical or subtropical fauna of the present day, 

 and the Blattida? which I have examined, belonging to 9 genera and 24 

 species, present no details of structure or form which we can regard as 

 peculiarly primitive and archaic. I have not found it necessary to erect a 

 single new genus for the reception of any amber-enclosed species, for all are 

 plainly referable to genera which flourish to-day in the tropical belt. The 

 chief interest of the collection lies in the comparison which it is possible to 

 make between the occurrence of certain genera in the amber-deposits and 

 their geographical distribution at the present time. The following are the 

 genera of Blattidse occurring in the amber-deposits : — 



Ectohius. ?iVyc^^&oy'« (larval form only). 



Ischnoptera. Periplaneta. 



Hhylloch'omia. ? Poli/phac/a (larval form only). 



Ceratinoptera. Ilolocompsa. 



Temnopte?'t/d'. 



* This is Bd. ii. Abt. 1 of tbe memoir * Organisclie Reste im Bernstein,' the first volume 

 iiaving appeared in 1845. 



