300 Annals Entomological Society of America [Vol. XV, 



The systematic position of the genus PcBromoptis has long 

 remained doubtful. Its features are so special that Bollman has 

 been led to create for it the family PceromopidcB, in which 

 Karsch's genus stood alone. But the question of its affinities 

 was not solved thereby. Silvestri, after having left the point 

 undecided, 1896S finally, 1898, admits Bollman's family 

 PceromopidcE amongst his luloidea. So likewise does Pocock^ 

 who denies it a relationship with the Bla?iiulidce and the Iso- 

 batidce. Attems, in his arrangement of the so-called "Protoiu- 

 lidcB," does not mention Karsch's genus^ 



That Pceromopus has to take place in the Paraiididi phylum, 

 will certainly not be contested; yet it has still to be decided if 

 it has to stand with the ParaiulidcB or with the BlaniulidcE'^ . 



If considered separately, the male genitalia supply no pos- 

 itive criterium. However, since the vulvae are somewhat better 

 known, it seems that a clue may be obtained from their struc- 

 ture. It has been mentioned that the vulvae of Pceromopus, 

 provided as they are with a shield, are of a type not usually 

 met with amongst luloidea. In fact the only species in which 

 a similar structure has been as yet observed, is Mesoblaniulus 

 serrula (Brol.), a tiny cave-dweller of the French Mediterranean 

 coast, originally ascribed to Blaniulus. In a paper actually 

 submitted to press^ an abstract of which" appeared recently, 

 the author has altered his first opinion mostly on account of the 

 conditions of the vulvae; consequently it has been brought to 

 rank amongst the IsohatificE. An identical reason will therefore 

 justify an attempt to enclose Pceromopus in the same group, in 

 which a new Tribe — Pceremopini — will have to be created for 

 its reception. No objection against such a conclusion can be 

 derived from the male genitalia of Pceromopus, as these show 

 the structure constantly found existing in Isobatince, i. e., the 

 preservation in the gonopods of a distinct coxal region, which is 

 missing in Blaniulince. 



iSilvestri, 1896, Ann. Mus. Civ. Stor. Nat. Geneva, (ser. 2) XVI, 26, III, 1896, 

 and 1898, Ibid, (ser. 2) XVIII, 29 XII, 1897. 



sPocock, Ann. Mag. Nat. Hist., (7) XII, No. 71, Nov. 1903, p. 527. 



3Attems, Arkiv. for Zool., Stockholm, 1909, V, No. 3. 



^According to the author's system, the BlaniulidcB are divided into two sub- 

 families, Blaniulince and Isobatince. 



^This paper was ended during the spring, 1921, but could not be issued owing 

 to the adverse conditions. 



^Arch. Zool. exper. gen., LX, Notes et Revue, No. 1, 1921. 



