LOUSE FAMILY TROCHILIPHAGIDAE — CARRIKER 311 



Undoubtedly the genus Ricinus is the progenitor of the abnormal, 

 Ricinus-likc form found on the Trochilidae, as well as the more dis- 

 similar Trochiloecetes, since both of these forms are unquestionably 

 blood-sucking parasites and hence degenerates. Further support for 

 this theory is found in the presence of Ricinus on such a large and 

 varied number of hosts, while the blood-sucking degenerates are 

 found only on the Trochilidae. 



In my own collection I have specimens of Ricinus from 16 passerine 

 families embracing 101 genera and 136 species. Three records from 

 nonpasserine hosts have been discarded as being probable stragglers. 



The original Ricinus-like form must have been parasitic on the 

 progenitor of the hummingbirds at a very early stage of its existence, 

 and, not finding their type of feathers suitable food, must have gradu- 

 ally developed the present type of piercing mandibles and the very 

 complicated sucking apparatus, an evolutionary process which must 

 have been extremely slow. 



Such a difference in the most basic anatomical character of these 

 insects certainly entitles the group to special nomenclatural distinction. 

 I therefore propose a new family for the two groups parasitic on the 

 Trochilidae, viz., the genus Trichiloecetes and those species which are 

 now called (incorrectly) Ricinus but which should be given generic 

 distinction. 



Suborder Amblycera Kellogg, 1896 



Family Trochiliphagidae, new family 



Type genus: Trochiloecetes Paine and Mann. 



The outstanding characters of this family are the minute, more or 

 less fixed, piercing or scarifying mandibles and the complicated 

 sucking apparatus lying between them. The mandibles of Tro- 

 chiloecetes are L-shaped, with their attachment at the angle of the 

 L, the short piercing arm pointing inward and the long arm backward 

 (for further details see under the genus, below) . 



The mandibles of the new genus, Trochiliphagus are minute, roughly 

 cone-shaped, with irregular outline and usually blunt points and with 

 bases fused to the nodi, to which are attached the palpi (see also fig. 2). 



The sucking apparatus is supported by a very complicated frame- 

 work, differing considerably from species to species. The sucking 

 portion consists of a needlelike tube, tapering slightly to a slender 

 point and lying within a sheath open at the apical end. The sheath 

 is composed of two portions separated distally and ending in very 

 slender tips, so that there seems to be three stylets. 



The sucking apparatus bears a certain resemblance to that found in 

 Anoplura. In the new family, however, the sucking apparatus lies 

 completely within the head, is accompanied by a pair of piercing 



