56 Annals Entomological Society of America _[Vol. VII, 
RESPIRATORY SYSTEM. 
The Coccids possess a respiratory system that seems to 
be nearly uniform through the entire group, and that found in © 
this species varies little from that of the larger representatives of 
the family. It consists, in Epidiaspis, of two pairs of stigmatic 
openings or spiracles, well guarded by hairs and spinneret- 
like glands which excrete a powdery wax over the exterior 
opening. These apertures (Plate XII, Fig. 6) possess 
rosettes (6-b) that make them indistinguishable from those 
that surround the vulva. A short tube leads from the stigma, 
opening into a chamber from which numerous tracheoles’ 
radiate, always, however, in a definite way so that all the 
individual insects of that species show the same character- 
istics and design (Plate VII, Fig. 2). For the most part these 
tubes are confined to the ventral surface, but can often be traced 
into the body cavity, surrounding the different groups of organs. 
The degree of diffusion of this system and its limit of ramification 
could not be determined, as only those tubes that possess a 
chitinization can be positively identified in the sections. In 
the larger, less specialized forms of Coccids, taenidial rings, 
the familiar characteristic of tracheal tissue are found, but 
in this species no such rings were noted, though a careful 
search for them was made. The characteristic trunk con- 
nectives joining the spiracles are very small and as a rule 
are unbranched. In some Coccide these have been found to 
be wanting, undoubtedly the result of degeneration. 
THE CIRCULATORY SYSTEM. 
The scale insects as a whole seem to be lacking in anything 
that may be called a definite circulatory system. No trace 
of a dorsal vessel can be found and no movement or pulsation 
of the body was noted that would indicate the presence of 
any such system. 
