108 Mr. F. Holme 07i the Habits, 



genera belonging to the order whose transformations are unknown; 

 and the observations of Stein and Macquart upon the pupae of the 

 latter are sufficient to prove that these aquatic insects cannot be 

 the larvae of Boreus, There remains, however, to be noticed the 

 anomalous genus Jcentropus, respecting whose order entomo- 

 logists are so much at variance. It is barely possible that they 

 may be the larvae of that genus. Without, however, deciding 

 that these insects have not arrived at their perfect state (in which 

 case the name Branchiotonia Spongillce may be applied to them), 

 it may perhaps be the most advisable course to regard them as 

 larvae of some extraordinary group not hitherto detected, and, at 

 the same lime, to express a hope that persons having an oppor- 

 tunity of examining the Spongilla will endeavour to trace the 

 transformations of this perplexing species. 



XVIII. Rough Notes on the Habits, Manners, &^c. of some 

 of the British Brachelytra. By F. Holme, Esq., M.E.S. 



[Read 5th March, 1838.] 



The division Coleoptera Brachelytra of Latreille, (corresponding 

 nearly with the old Linnaean genus Staphyllnus,) is one of the 

 most curious and interesting groups, in the variety and singularity 

 of its forms, and the various localities and pabula frequented by 

 its different genera, which our Coleopterous Fauna comprises : 

 while in the number of its indigenous species it far exceeds any 

 other British division of equal rank among the Coleoptera ; its 

 strength in this respect nearly equalling the united forces of the 

 Geodephaga and Rhynchophura, the two groups which most nearly 

 approach it in point of numbers. The metropolis, indeed, of the 

 Brachelytra is said by Kirby and Spence to be, " as far at least 

 as we can judge from our present catalogues, within the tempei'ate 

 zone, particularly in Britain." Dejean, in his catalogue, gives 

 only 434* species : while Mr. Stephens, whose cabinet might 

 contain in 1828, according to the supposition of Kirby and Spence, 

 above GOO species, enumerated no less than 852 in his invaluable 

 Systematic Catalogue published in 1829, which he increased to 

 892 in the second edition of his Nomenclature, published in 1833. 

 Notwithstanding this vast increase from the numbers of Marsham, 

 who in 1802 could record only eighty-two species under the 



* In the edition of 1833, Dejean gives 789 species, European and exotic — 

 Enlom, Edin. 



