BY THOMAS G. SLOANE. 315 



(4)The humeral depression of the elytra; on each side of the base 

 of the elytra, just behind the basal angles of the prothorax, there 

 is usually a more or less developed longitudinal depression, 

 often punctate; it is very deep in Therates. In our fauna the 

 humeral depression varies considerably; in all the species of 

 Megacephala with the basal part of the elytra unicolorous it is 

 obsolete; but it is present in the species with the lateral margins 

 brownish or testaceous (most feeble in M. crucigera); in Distyp- 

 sidera it is strongly developed; it is present in Rliysopleura; in 

 Cicindela it varies, being well developed in the iosceles- and 

 doddi-groups which come nearest Distypsidera. It is probably 

 a secondary sexual character originally pertaining to the female, 

 correlative with the deeply concave mesepisterna in many species 

 of Cicindela, and the protuberant posterior angles so strongly 

 developed in C . aurita. 



Phylogeny. 



Dr. Walther Horn, in his " Index," has some notes on the 

 phylogeny of the Cicindelidse, from which I take the following 

 interesting hypotheses — (l)The earliest Cicindelid-like form 

 appeared in the Tropics of the Ethiopian region, branching from 

 a Carabid-stem. (2)The Paleomantichorini, &c, followed by the 

 Megacephalini, &c, leading on to the Cicindelini (geologically 

 the most recent Cicindelid-form) may be taken as the general 

 line of descent. 



Dr. Horn believes that the original Cicindelid-forms were 

 wingless, but there appear to be such strong objections to this 

 idea that I cannot follow him on this point. I do not propose to 

 elaborate arguments against the descent of strong-flying species 

 from wingless ancestors amongst the Coleoptera; but J believe it 

 will be impossible for anyone to accept the conclusion that the 

 earliest Cicindelid-forms were wingless, who holds with me the 

 following opinions — (l)Thatthe Coleoptera are descended from 

 insects with four free wings. (2)That the earliest Coleoptera 

 were winged. (3)That the loss of the underwings indicates a 

 degradational form among the Coleoptera. A nd (4)that characters 



