Species o/Eiioceia in the British Museum. 79 



on its outer surface a groove into which the outer clasper 

 fits. The two pairs articulate together at the tip of the side- 

 piece, and are movable in a horizontal plane. 



Tlie tenth (anal) segment, as in most Limnobiidre, is a 

 spicular tube of tough membrane, usually entirely devoid of 

 chitinisation and retracted beneath the ninth tergite. Very 

 rarely a pair of small tergites bearing a few bristles are 

 pr<'sent. I have seen no indications of cerci, though in some 

 Limnophilinse these are represented by terminal papillae. 



The cedceagus (see text-fig, 2, h) is highly chitinised and 

 complicated, and is probably in a much more generalised 

 condition than that of the Culicidse. In the main^ the 

 general conception of the genital tube given by Sharp and 

 Muir for tiie Coleoptera (Trans. Ent. Soc. London, 1912, 

 p. 602, fig. 239) will fit that of Eriocera very well. The 

 main differences lie, firstly, in the fact that in Eriocera the 

 mesosome (median lobe) is permanently invaginated, and, 

 secondly, that there is a strong chitinisation of prtrt of 

 the " first connecting membrane^' between the mesosomal 

 and tegminal rings of the genital tube. 



On the dorsal side of the sedceagus, continuous, on the 

 one hand, with the second connecting membrane (at the 

 base of the tenth segment) and, on the other hand, with 

 the tubular penis, is a large chitinous structure, whose 

 homologies are somewhat uncei'tain. It might be possible 

 to regard it, or part of it, as the tenth sternite, and its 

 appendages as anal cerci, but from the fact that it never 

 bears any bristles, also because it is in contact or fused 

 laterally with the basal plates, I think it must certainly be 

 regarded as part of the tegminal ring of the genital tube. 

 'J'his is also indicated by its readiness to take up stain, 

 quite unlike the chitinisations of the body-wall, but agree- 

 ing in this respect with the rest of the genital tube. It 

 bears a pair of processes (paranieres) , which in their free 

 portion are very variously constructed ; at the base these 

 processes spread out, and are fused laterally with processes 

 from the base of the side-pieces and medially with one 

 another. The median fused portion forms a strong bar 

 connecting the bases of the side-pieces, and extends almost 

 vertically downwards to the base of the penis ; in the dorsal 

 portion of this median structure there are distinct traces of 

 fusion, but none at all in the ventral portion. The pair 

 of processes are undoubtedly homologous with the gona- 

 pophyses of de Meijere and others, which I have.elscAvhere 

 identified with the parameres ; this identification is possibly 

 incorrect, since in the Culicidai the paiamercs are articulated 



