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SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 82 



I 



Orthoptera, Hemiptera, Coleoptera, Diptera, Lepidoptera, and Hy- 

 menoptera. Under his general conclusions he states that some authors 

 believe that the discharged liquid is blood, while others think it is a 

 glandular secretion. The manner in which the liquid is discharged 

 is little known, except in a few cases. In general it is admitted that 

 the blood is discharged by a reflex action, being a means of defense. 

 He discusses four methods in which the blood is discharged and gives 



Fig. 19. — Drawings, illustrating reflex "bleeding" in lady-beetles. A, diagram 

 of a section through fenioro-tibial articulation of Epilachna borealis, showing fol- 

 lowing: a, pores of gland cells without reservoirs; BS^ blood sinus; H, mem- 

 brane dividing lumen of leg into two chambers ; Po, pores of gland cells having 

 reservoirs ; and St, sense hairs. B and C, portion of tubercle on larva of bean 

 beetle; B, distal end of tubercle having 6 branches (Br), each of which is 

 terminated with a hair (Hr), X 32; and C, distal end of a branch, showing hair 

 arising from a socket, which is surrounded by 5 processes (Pr), only 2 being 

 shown, X 320. 



examples of insects for each method. He further remarks that the 

 ejected blood is usually very toxic. 



While discussing coleopterous larvae, Hollande shows how coc- 

 cinellid larvae protect themselves by discharging blood. As an example 

 he used Epilachna argus, whose body is covered with chitinous tu- 

 bercles, which in turn bear many smaller branches, each of which 

 is terminated by a hair. The discharged blood is accomplished by a 

 rupture of the chitin near the base of the hair. When one seizes the 



