796 CHARLES PAUL ALEXANDER 



heterogeneous assemblage, but in reality it constitutes a natural group. 

 The tribe as herein arranged includes the old group Limnobiini, with the 

 addition of several genera that were formerly distributed in the Antochini. 

 The -divisions of the tribe as now constituted are as follows: 



1. Limnobaria including the old tribe Limnobiini. 



2. Ellipteraria including the genus Elliptera. This is close to the 

 preceding subtribe and may be a group belonging to it. 



3. Antocharia including Antocha and presumably allied genera, as 

 Orimargula, Orimarga, Diotrepha, and possibly others. 



4. Rhamphidaria including Rhamphidia and its allies. 



5. Dicranoptycharia including Dicranoptycha only. 



These groups are not far removed, phylogenetically, from the lowermost 

 divisions of the Hexatomini, such as the Ularia and the Epiphragmaria, 

 and the two tribes are unquestionably closer together than their arrange- 

 ment on paper would indicate. The separation of the two major groups 

 was made largely on the characters of the imagines. 



The larvae have the body terete, moderately elongate or very long and 

 slender (Dicranoptycha). The abdominal segments are subdivided into 

 a basal and a posterior ring, the former with transverse welts of micro- 

 scopic chitinized points or hooks. In the Limnobaria and the Antocharia 

 these welts occur on both the dorsal and ventral surfaces in the form of 

 microscopic hooks; in the Ellipteraria they are on segments 3 to 9 on the 

 dorsal surface only, being indicated on the ventral surface but naked; 

 in the Rhamphidaria the welts are ventral in position on segments 2 to 

 7; in the Dicranoptycharia they are similar, on segments 2 to 8. The 

 body in Dicranoptycha is entirely glabrous. 



The head capsule is of moderate to large size and is massive and com- 

 pact, consisting of a narrow dorsal plate which is usually indented behind, 

 arid two broad mussel-shaped lateral plates which are connected ante- 

 riorly across the venter to form the mental plate. The mental plate 

 consists of an outer plate which usually terminates in a single median 

 point, and behind this an inner plate which contributes additional teeth 

 to the mentum. In Dicranoptycha there is but one subequal tooth on 

 either side, with an additional much-reduced tooth; in Rhamphidia 

 there are two teeth, and in the other groups there are usually four or five. 

 The hypopharynx is usually a double plate united at the ends to form 

 a collar, with the anterior margins finely toothed. The maxillae are 



