36 Dr. Karl Krapelln on the Pulicidse. 



V. — On the Systematic Position of the Pulicidas. 

 By Dr. Karl Krapelin*. 



[Plate ni.] 



After my investigations on the buccal organs of the Diptera 

 and Rhynchota + had led me to the conclusion that in the 

 former the true sucking-tube (not to be confounded with the 

 labium, which serves only as its sheath) was formed by a 

 dorsal and a ventral half-gutter (labrum and hypopharynx), 

 and in the latter by two double half-gutters laterally inter- 

 locked, it seemed natural to study also the aberrant members 

 of the two series in the light of this criterion, which ap])lied 

 to all typical forms, in order to arrive at greater clearness 

 with regard to their relationships. In this respect no small 

 interest undoubtedly attaches to the group Pulicidffi, which, 

 notwithstanding much difference of form, presents such a 

 uniformity of organization, and as to the systematic position 

 of which for more than a century the most different opinions 

 have been expressed, without any generally acceptable and 

 well-established view having yet been arrived at. 



The history of these opinions has ah-eady been given 

 pretty completely by Taschenberg in his Monograph on the 

 Fleas J, so that here a short recapitulation may suffice. 



Linn^, as is well known, created an order Aptera for the 

 wingless insects, Myriopods, Spiders, &c., and in this the flea 

 found its place. A simihar position was assigned to it by 

 Geoffroy, Cuvier, and Dumdril, as also by Gervais ; while, on 

 the other hand, the order Aptera was by many rejected as 

 unnatural, and the relationship of the Pulicidse with various 

 winged insects was asserted. Thus Kircher referred them to 

 the Orthoptera, Fabricius and Illiger to the E-hynchota, Rosel, 

 Oken, Strauss-Durckheim, Newman, Burmeister, Walker, 

 Von Siebold, and others to the Diptera. Lastly, there were 

 also very early naturalists who would associate the flea with 

 none of the existing orders of insects, but postulated a distinct 

 order for it. The leader in this direction is De Geer. He 

 was followed by Lamarck, Latreille, Kirby and Spence, 

 MacLeay, Leach, Dug^s^ Bouchd, and Van der Hoeven, and, 



* ' Festschrift zum 50-jaliiigen Jiibiliium des Realgymnasiums des 

 Jolianneiims,' Hamburg, 1884. Translated by AV, S. Dallas, F.L.S, 



+ In part set forth in the preliminaiy communication "Ueber dio. 

 Mund-werkzeuge der saugenden Insekten" (Zool. Anz. 1882, pp. 674-79) 

 and in a memoir, "Zur Anatomie und Physiologie des Eiissels voii 

 Musca " (Zeitschr. f. wiss. Zool. xxxix. pp. 683-719). 



X Taschenberg, 'Die Flohe ' (Halle, 1880). 



