1909.] NATURAL SCIENCES OF PHILADELPHIA. 35 



made to designate it by any especial term, except that Comstock, '04, 

 terms it the antecoxal piece. This, however, is not the antecoxal 

 piece of Comstock, '02, nor of Walton, '00, and most assuredly does 

 not represent the antecoxal plates of Leconte, '61. 



In the Blattidae (pi. Ill), the furci-sternum of the meso- and meta- 

 thorax is somewhat "T "-shaped, and the internal paired apophyses are 

 borne one at the end of each arm of the "T". Each of the outer 

 openings of the hollow apophyses is covered by a sclerite which may 

 be termed the "tegmentary sclerite" (pi. Ill, Tg). The function 

 of these "tegmentary" sclerites is doubtless to keep dust, etc., from 

 collecting in the hollows of the apophyses. Miall and Denny, '86, state 

 that there is no ante-furca (i.e., prothoracic furca) in the cockroach; 

 nevertheless paired apophyses which correspond to the meso- and 

 meta-thoracic furca are to be found in the prothorax, if sufficient care 

 be taken in searching for them. The specimen should be slit along 

 the mid-dorsal suture, placed in 10% caustic potash, and left in the 

 paraffin oven until the soft parts can be easily washed away by driving 

 currents of water against them with a pipette. If the soft parts are 

 removed with forceps the apophyses, which are very delicate and 

 somewhat transparent, are usually plucked off before one discovers 

 them. This doubtless accounts for the fact that these structures were 

 not found by Miall and Denny. 



The prothoracic furci-sternum of Nemura (pi. I, S' 3 ) is divided into 

 two pieces; in the Trichoptera (fig. 18, S' 3 ) it is a single plate, drawn out 

 longitudinally, while in the Blattidse (pi. Ill, S' 3 ) it is a somewhat 

 oval transverse sclerite. 



In the meso- and meta-thorax, the furci-sternum is frequently 

 separated from the basi-sternum merely by the "intra-sternal" suture. 

 The furci-sternum is usually connected with the katepimeral complex 

 by the narrow antecoxal laterale (fig. 3, L b ), and may likewise be 

 connected with the epimeron by a bridge-like strip extending behind 

 the leg. In the Trichoptera (fig. 18) this strip (S" 3 -Em") dips below 

 the surface of the body, and reappears just before it is joined with 

 the epimeron. In those insects in which the coxal cavity is enclosed 

 posteriorally the coxae are frequently closely approximated, and that 

 portion of the furci-sternum between them is folded together. This 

 is well shown in the Trichoptera (fig. 18), and in these insects the 

 "pedal region" of the furci-sternum (S" 3p ) extends along the mesal 

 surface of the coxa, with which it is very closely connected. 



It is perhaps of some interest to note that in the Trichoptera the 

 pleural suture is continued in the "coxal suture" (between the meron 



