502 



NEW YORK STATE MUSEUM 



The type' specimens are well preserved and leave no question 

 as to the identity of the species. A very full series including repre- 

 sentatives of 13 varieties is contained in the Fitch material in the 

 National Museum. 



Reported from Buffalo on birch [Van Duzee, Buf. Hemip. p. 

 144]. Evidently generally distributed. 



Bythoscopus sobrius Walk. 



Bythoscopus sobrius Walk. Homop. 1851. 3:874; Fitch, 

 reprinted in Lintner. 9th Rep't. 1893. p. 400; N. Y. State Agric. Soc. 

 Trans. 1858. 18: 853 



Bythoscopus sobrius Van Duzee. Buf. Soc. Nat. Hist. Bui. 



4, p. 19S. 

 Recorded by Van Duzee for Golden, Lancaster. 



1 There is an interesting question regarding the types of Fitch's species 

 and one which it seems rather difficult to settle. The paper on Homoptera 

 published in the New York State Cabinet Catalogue in 185 1 includes the 

 numbers arranged serially according to -the species described. ^ These num- 

 bers agree with numbered specimens which were deposited in the _ State 

 Cabinet of Natural History, which specimens have since remained in the 

 custody of the Museum. So far as preserved they are unquestionable ex- 

 amples of these species as indicated by Dr Fitch himself and whether termed 

 "types" or not they must be considered as equivalent to types in their 

 authority. Dr Fitch's private collection which included examples of species 

 that he described was broken up but the Homoptera were finally purchased 

 by the United States National Museum and specimens of Jassidae bearing 

 Fitch's labels which have for Fitch's species been marked with type labels, 

 stand now in the National Museum collection. 



They do not, however, bear numbers which correspond with the published 

 catalogue so that it has appeared "to me that the published evidence would 

 favor the Albany specimens as the types. Mr Schwarz tells me, however, 

 that Fitch's descriptions were drawn from specimens numbered to corres- 

 pond with numbers in his notebooks and that these numbers are the 

 most positive basis of recognition of the specimen from which the original 

 description was drawn. Such numbers occur on the Psyllidae and speci- 

 mens in some other groups but on examination with this point in view it 

 turned out that the Jassids, at least for all species examined, do not contain 

 a Fitch number. 



It is to be noted that in certain species, as for instance I d 1 o c e r u s 

 lachrymalis, the Albany series is complete for not only typical 

 forms but for all of the described varieties, whereas the Washington series 

 includes an example of but one form. On the other hand, for By- 

 thoscopus variabilis the Washington series is by far the most 

 complete including representatives for the described varieties whereas the 

 Albany collection includes but one (?) form, all the varieties having been 

 omitted or subsequently lost. Fortunately so far as observed, there is 

 close agreement between these specimens in the two collections, a fact which 

 would be expected from Dr Fitch's well known care and hence the question 

 of the validity of the type specimen becomes less important. 



It appears to me, however, that on the whole it would be best since the 

 Albany species bear definite numbers agreeing with the published descrip- 

 tions to consider these as types and the other specimens as cotypes. It at 

 least seems the rational course to pursue for such specimens in the National 

 Museum as, while bearing labels written by Dr Fitch, do not possess numbers 

 which would identify them as the particular specimens from which the 

 descriptions were written. 



