AMERICAN PSYLLlDyE II (Triozin^) 



BY 1). L. CRAWFORn. 



In studying a group which has been only locally systematized, one is 

 apt to find that the anatomy of the species of the group is quite inadequately 

 known. Dr. Franz Low has published an article on the anatomy of the 

 i'syllidae in which the nomenclature of most of the external anatomy is given. 

 The thoracic and ventral anatomy, however, is not very thoroughly known 

 and, therefore, not used in diagnosis. In order to bring out more clearly 

 some of these little known characters and make them available for diagnostic 

 use, another paper is being prepared on the external anatomy of the Triozin.e. 

 Several structures have been noted in the course of this study which have 

 liitherto been scarcely mentioned or figured in specific descriptions. Chief 

 among these is a remarkable horn-like spur on each meta-coxa, and sometimes 

 another pair distinct from these and extending in the opposite direction, 

 (Fig. 128 i). These are present in Ijoth sexes and will perhaps ofifer a 

 good character for separation of minor groups of species, at least. 



In this paper the specific descriptions begun in the first article are continued. 

 It is (|uite possible that a further anatomical study will reveal characters which 

 will have to be added to these mentioned in this paper. 



Trioza collaris n. sp. 



(Figs. 128 A, B; 129 A; 130 A.) 



Length of body with ovipositor, 2..t mm. ; without ovipositor, 2.3 mm. ; 

 length of forewing, 3.8 mm.; greatest width of forewing, 1.6 mm.; width of 

 vertex between eyes, .44 mm. ; with eyes, .72 mm. General color, greenish 

 yellow. 



Head moderately deflexed ; with eyes not quite as broad as thorax ; 

 finely punctate. Posterior margin of vertex arcuate, narrowly elevated over 

 middle half ; discal area of frontal plates with a distinct fovea midway between 

 median suture and posterior ocellus on each side, with a diverging depression 

 extending down toward face ; frontal plates not raised plate-like, scarcely 

 emarginjtte anteriorly at median suture. .Anterior ocellus at angle of facial 

 cones and under the slightly overhanging vertex, not visible from above. 

 Facial cones short, scarcely divergent, acute at tip, subhorizontal but not visible 

 from above, sparsely pubescent. Antennae inserted at base of facial cones, 

 without, beneath eyes ; two basal segments large, subglobose ; remaining seg- 

 ments destroyed. 



Thorax arched, finely punctate ; pronotum long, not depressed below 

 dorsulum and head. Dorsulum strongly ascending, about as long as scutum, 

 with a light brownish stripe on each side ; scutum with a double strijie on 

 each side a little darker than ground color. Wings hyaline, about two and 

 one-half times as long as liroad, broadest across first marginal cell, rounded 

 apically : radius longer than second cubital ; marginal cells subequal ; apex 



