128 Annals of the Carnegie Museum. 



Sao Sebastiao in 1900 by A. Hempel, 1 d\ Academy of Natural 

 Sciences. 



The original description states that this species is " Presque sembable 

 a 1' A. Claussenii," after which remark some differences from claussenii 

 are given, without any mention of the abdomen. The abdomen of claus- 

 senii is described as blue, " Les segments 2e-2>e termines et bordes 

 lateralement de noir. Cette couleur occupant plus d'espace sur les 

 derniers. " One might, therefore, have expected a larger area of blue 

 on the abdomen of sordida than examination of the cotypes described 

 above proves to be actually the case. 



44. Argia fosteri sp. nov. 



(Plate IV, figs. 58, 69, 69^-.) 



d\ Rear of the head chiefly pale, with distinctly less or almost as 

 much black around the occipital foramen. Pale (blue) antehumeral 

 stripe half to three-fifths as wide as the black mid-dorsal. Black hu- 

 meral stripe forked in its upper half or third, both branches of the 

 fork reaching to the upper margin of the sclerite ; below the fork the 

 humeral stripe is a little wider than the pale antehumeral. A brown 

 line on the whole length of the second lateral thoracic suture except 

 at the upper end which is black. Abdominal segment 2 blue, with a 

 black stripe on each side from end to end, widened mesad at four-fifths 

 of the segment's length toward, but not meeting, its fellow of the op- 

 posite side, the mid-dorsal blue on the anterior part of the segment 

 being half as wide as the segment, or the right and left black stripes 

 may fuse on the dorsum for the hindmost third of the segment and the 

 mid-dorsal blue on the anterior two-thirds is reduced in width ; often 

 from the inferior edge of each lateral black stripe there extends back- 

 ward (caudad) an oblique fork or branch toward or to the inferior 

 margin of the segment at about two-thirds of its length. Abdominal 

 segments 3-7 black, with a transverse basal blue ring which on 3-5 or 

 6 is produced, tapering backward, as a mid-dorsal stripe reaching to 

 two-thirds or one-half of 3, one-fourth to two-fifths of 4, and one- 

 fifth of 5 and 6 ; the inferior lateral margins of 3-7 narrowly blue, 

 except in the hindmost fourth to sixth of each segment ; 8-10 blue, 

 with an inferior black stripe on each side as long as the segments, or 

 not occupying the most anterior third of 8 ; in some a pair of poste- 

 rior dorsal black spots on 8. 



