THE imm \ I i i;i STA I i: OF I HE ODON VIA. I , 



length, lo very short, small, cylindrical, almost wholl} inserted in 9 ; lateral 

 spines .in segments 8 and 9 triangular, flat, straight, tip very sharp; lateral 

 Bpines on segment 8 short, half the length of 9 ; those on 9 as long as 

 tlif anal appendages; the lateral Bpines belong to the dorsal part of the ab- 

 domen, as is shown by a suture on the ventral side, running very near the 

 side margin. Dorsal hooks -tout on segments - to 9 or 10; on "J to I nar- 

 rower, erect, more cylindrical; on the following ones compressed, their 

 bases being connected with about the whole Length of the segment; their 

 tip seen sideways triangular, sharp, pointing towards the end of the abdo- 

 men; when present on segment LO, small, as an elevated ridge, the blunt tip 

 sometimes extending beyond the segment. The anal appendages, a little 

 longer than the lust segment, form together a short pyramid ; the dorsal me- 

 dian about as long as the inferiors, triangular, broad; in the male, the upper 

 basal portion inflated ; the inferiors pyramidal, sharp : the laterals smaller, 

 sharper, shorter, or as long as the dorsal median. The ventral side of the 

 abdomen Hat, with two longitudinal sutures ending in the apical inner 

 angle of segment 9 ; the central and lateral parts of the venter about 

 equal ; on the base of segment 6, on each side, in the lateral space, a 

 deep transverse opening for the entrance to the ventral bag; the abdom- 

 inal stigmata small ; the genitals very slightly marked ; hind legs far apart 

 at base, a little more so than middle legs ; fore legs nearer together ; just 

 behind the hind legs a transverse ridge with a round or oval median 

 tubercle ; legs very long, successively longer, the femur of hind legs reach- 

 ing the ninth segment or beyond ; thin, cylindrical, femur slightly flat- 

 tened, as long as the tibia, or longer ; tarsus about half as long as the tibia, 

 three-jointed ; first joint very short, the two others long, equal in length ; 

 claws as long or shorter than the last joint, thin, very sharp, slightly bent; 

 the bifid character of the claws of the imago is not indicated in the nym- 

 pha. Thorax and abdomen often variegated with gray and white, forming 

 a series of ill-defined spots; femur generally has three black bands. During 

 the transformation, the anterior curve of the split of the skin near the 

 eyes passes through the non-facetted portion, which surrounds the eyes 

 anteriorly. 



Of the subgenera of the large genus Macromia, as accepted in 1878 by 

 De Selys in his Second Additions to his Synopsis of Cordulina. the twenty- 

 three first species belong here, to which one new species from Borneo 

 may be added. Six species of those recorded are from the United States. 



