CALIFORNIA ACADEMY OF SCIENCES. 35 



(Biol. Cent.-Amer., I, Ft 2, p. 506), probably because of 

 this variability, considers the palpal structure as of minor 

 importance when compared with others, and does not even 

 employ it in subdividing the genus, although this has been 

 done with more or less success by Dr. Le Conte (Proc. Am. 

 Phil. Soc. XYII, 1878, p. 390), but without considering the 

 structure of the maxillary palpi, we still have, I think, 

 enough characters remaining to confirm the validity of Hes- 

 perobium. 



Dr. Sharp, in the work above mentioned, divides the 

 Central American species into groups depending upon the 

 presence or absence of a lateral raised line upon the lower 

 part of the flank of each elytron; when the Paederini have 

 been sufficiently studied as a group, it may be found desira- 

 ble to give this character a generic import, in which case 

 the name Hesperobium should be retained for the species 

 having this lateral line, as it is present in the type which is 

 assumed above as representing the genus. It is also present 

 in califormcum, and in an undescribed species, represented 

 in my cabinet by a unique male, found near San Francisco; 

 it is probably characteristic of the Calif ornian species as a 

 group'. 



In describing several species of this genus (Cent. II, pp. 

 1'27-133), attention was called to two very large and promi- 

 nent annular punctures, or more properly areolae, situated 

 behind the eyes. I think that these punctures are of greater 

 importance from a systematic standpoint than was at first 

 supposed, as they constitute one of the distinguishing fea- 

 tures of Hesperobium and the ilmerican species of Lathro- 



iu Hynonjmj, I take the present opportunity to say in addition, that it is 

 very difficult to reconcile Dr. Horn's assertion regarding the mutual identity 

 of my H. capito and H. pallipes, Grav., with the statement made by Erichson 

 in the description of the latter, viz: " Thorax latitudine sesqui fere longior." 

 The prothorax in cax^ito is "scarcely one-fifth longer than wide." (Cont. II, 

 p. 128.) 



3 This line is also well developed in the Californian species which have 

 been referred to Lathrobium and which are probably generically distinct. 



