( 157 VIII . On the external sexual apparatus of the males of the genus Acentropus. By Robert M'Lachlan, F.L.S., Sec. Ent. Soc. [Read 1st April, 1872.] At the Meeting of this Society held on the 4th ultimo, my friend Mr. Dunning read a memoir (see preceding paper) on the genus Acentropus, which I propose to sup-plement by some remarks of my own, on points avowedly not investigated by him. Of the ordinal position of the genus I say nothing, except that I thoroughly agree with those entomologists who place it in the Lepidoptera, feel-ing sure that the few who appear to doubt the correctness of this opinion, can never have studied the characters, or, if they they have done so, maintain a factious opposition from pure affectation. As a Trichopterist, I assert that the attributes of the genus, its structure, larval characters, and, in fact, everything excepting its aquatic habits, are utterly opposed to its being Trichopterous, whereas there is nothing whatever incompatible wiLh its ordinal position in the Lepidoptera. Before proceeding to the subject of this paper, I will remark, en passant, concerning Mr. Dunning's observa-tions regarding the existence or non-existence of ocelli. Kolenati asserted the presence of two undoubted ocelli in the ordinary position on the front portion of the vertex. I have no hesitation in declaring these ocelli to be fic-tions. At a seance alluded to by Mr. Dunning (see p. 129) at which he, myself, and Mr. Douglas were present, we subjected several examples to minute mi-croscopic investigation, after having carefully denuded the heads of every vestige of scaly clothing. The result proved that in the position assigned by Kolenati, there were no signs whatever of ocelli either developed or abortive. But, in a slight depression on the outer side (that next the eye) of the base of each basal joint of the TRANS. ENT. SOC. 1872. — PART II. (mAY.)
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