2 Mr. Gilbert J. Arrow's Contribidimt to the 



unpalatable ir. a high degree, like the neai^est related family, 

 the Coccinellidae, and that an offensive fluid is exuded by 

 many, as is the case with the largest species, Eumorphm 

 marginatus, which Mr. Bryant informs me is remarkable 

 for its extraordinarily strong and offensive odour, i sus- 

 pect it will be found that the characteristic grooves upon 

 the pronotum are the channels into which this secretion is 

 discharged (as Dr. G. A. K. Marshall has found to be the 

 case in the Histeridae), and that the basal loveae when 

 fully developed conceal the orifices of the secretory glands 

 These depressions, Avhich form one of the best-marked and 

 most constant features of the group, are more or less tunnel- 

 shaped and are always deepest just withm the basal margin. 

 At the deepest part the appearance of a pore is sometimes 

 visible under the microscope. . , , ,• 



Dr C J Gahan, in his account of the stridulatmg organs 

 of the Coleoptera, has indicated an important group charac- 

 ter of this family in the presence or absence of a stndulatory 

 apparatus between the head and pronotum (Trans, l^nt. 

 Soc Lond., 1900, p. 436). He has mentioned that the exist- 

 ence of the organ distinguishes the Eumorphites, Coryno- 

 malites and Lycoperdinites of Chapais, but various genera 

 of the 3rd division must be excluded from this statement 

 such as Dapsa, Phalantha, Saula, and Danae. This 3rd 

 division, however, is tiuite an unnatural one, and a more 

 satisfactory arrangement is obtained by adopting Gerstaec- 

 ker's three Tribes, Eumorphini, Dapsini and Endomychim, 

 and treating the presence of the stridulatmg organ as the 

 primary distinctive character of the first, instead of the 

 shape of the antennal club, which is a very inconstant and 

 unreliable feature, hiddmus, Ancylojms, Lycoperdma, 

 Hiilaia {Cercmis), Acinaces, and Mycetma, as well as 

 PJiaeomychus and other genera of recent date, will then ]oin 

 the Eumorphini. In the more typical genera of that group, 

 with which Indalmus and Amylopus should be associated, 

 the 3rd joint of the antenna is much longer than those 

 immediately preceding and succeeding it, whilst m the 

 remainder this great disproportion vanishes. The relative 

 length of these joints is much more reliable than that ot 

 the club-joints and serves for the further division of the 

 Eumorphini. ^ , . . „ 



In the ordinary position of the head the microscopically 

 fine stridulatory file, in the genera possessing it, hes 

 beneath the margin of the pronotum and is not visible, 



