THE OLFACTORY SENSE OF COLEOFTERA. 



453 



soon became sick and died, while others lived thereafter for 

 many days. When tested with odors, most of the beetles without 

 antennae failed to respond, but Hauser states that Carahus, 

 Melolontha and Silpha still responded to odors, although more 

 slowly. 



CU 



SCNu 



PorPl MPPg PcrPI 



SF 



— -H 



HypNuc— \» Mrx 



D 



^ 



Fig. 3. Antennal organs of the water heetXe, Dyliscus marginalis, copied from 

 Hochreuther (1912). A, small tactile hair (Sinneshaar) from first segment of an- 

 tenna, total preparation (Fig. i from Hochreuther), X 330; B, portion of Fig. 12 

 from Hochreuther, showing four small sense bristles (Sinnesborsten) from proximal 

 end of second segment of antenna, X 265 ; C, longitudinal section (Fig. 48 from Hoch- 

 reuther) through a hollow pit peg (hohlen Grubenkegel), X 470; D, longitudinal 

 section through a small massive pit peg (massiven, grubenstandigen Zapfen) and 

 two pore plates (kelchformige Organe), X 590. This drawing is a combination of 

 Figs. 32 and 58 from Hochreuther. Only the pore plates {For PI) are taken from Fig. 

 58. Hochreuther gives a drawing of only one perfect pore-plate organ, or cup- 

 shaped organ, and it is from the maxillary palpus. CM, cup-shaped membrane; 

 HPPg, hollow pit peg; MPPg, massive pit peg; PorPl, pore plate; SB, sense bristle; 

 THr, tactile hair. See page 456 for other abbreviations. 



