A RE^^SION OF TIIE SOITTII AMERICAN DIPTEROUS 

 INSECTS OF TIIE FAMILY PTYCHOPTERID.E. 



By Charles P. Alexander, 



Of the Entoimlogical Laboratorij oj Cornell University, Ithaca, New Ynrh. 



The only genus of Ptychopteridje as yet made known from the 

 Neotropical regions is Tanydei-us Plulippi,' erected in 1865 to 

 receive the then unique species, pictus Philippi, of Chile. Two 

 New Zealand s])ecies, forcipatus Osten Sacken ' and annuliferus 

 Hutton,' have been described. The Cylirulrotoma onuitissima, 

 described by Doleschall from the East Indies in 185S, was later found 

 to be a true Tanydenis.* 



I have given, below, a rather free translation of Phihppi's original 

 description of T. pictus and also add the description of a fifth species, 

 tlie second from tiie American continent. 



KEY TO THE AMERICAN SPECIES OF TANTDERUS. 



Anal angle of the wing very sharp; wing with two brown faaciiB which are almost 

 unicolorous in all of the cells; antennse with at least 25 segments piclns. 



Anal angle of the wing less pronounced, square; wing with an irregular picture; dark 

 along the cro.ss-veins, much paler in the posterior cells of the wing; antennae 

 17-6egmented patagonicus. 



TANYDERUS PICTDS PhilippL 



Length body, 12 1.; wing expanse, 26 1. 



Head quite black, only the antennae are pale j'ellow, except the 

 first two segments, which, however, are black. The long, slender 

 neck-hke prothorax is also black and there appears above in (he 

 cephahc half a caniculatcd excavation, which is run through by an 

 elevated longitudinal line continuing to the posterior margin. The 

 anterior portion of the mesothoracic prscscutum is yellow with a 

 black spot in the middle ; the remainder of the mesothorax is, for the 

 most part, black ; on the pleurae, i n front of the %\ing basis, is a yellow 



' R. A. Philippi. Auliuihlung der Cbilenischen Diptcren, Verb, der Zool.-bot. Ges., 1865, vol. 15, pp. 

 780, 781, pi. 29, fig. Si. 

 « Verb. Zool.-bot. Ocs., 1879, p. 518. 

 > Tran-s. New Zealand Institute, vol. 32, p. 48. 

 ' Osten Sacken, Studies on Tipulidie, pt. 2, 1887, pp. 22S-230. 



