Preliminary Studies of the Internal Structures of Braula Coeca Nitzsch.*

The first mention of this insect was made in 1740 by Reamur (9), who discussed its relation to the honeybee. Nitzsch (1818) described the genus and species, naming the insect Braula coeca; and classified it, on account of its mouth parts, with the Diptera, associating it with the Pupipara. Errors in Nitzsch's description of antennæ and thorax were corrected by Egger (4), thus removing any doubt as to the alliance of Braula with the Diptera. Since Braula did not fit into any insect classification then in use, Egger proposed the special family, Braulidæ. According to Muggenberg (7), the structure of the head vesicle shows a close relationship between Braula and the Hippoboscidæ. Taxonomically, Handlirsch (5) removed the Braula from the Pupipara and placed it in a separate family next to the Phoridæ. It was formerly generally helieved that Braula coeca was pupiparous but, according to Muggenberg (7), Skaife (10), Arnhart (2) and Argo (1), it is oviparous. Skaife and Argo described fairly completely the life cycle of the insect, while Arnhart found the mines and dried out larval skins under honey cappings. Perez (Phillips 8) found that Braula was not a true parasite, as believed by the older workers, but that it was a sort of commensal parasite feeding on the nectar which it steals from the honeybee. Muggenberg (7) described the mouth parts and discovered the eyes of the supposedly blind insect in 1892. Borner (3) gives a detailed account of the external morphological structures. Skaife (10), through microdissection studies, described in a general way the alimentary canal and the male and female reproductive organs. He also worked out the metamorphosis of this insect.