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.