Section 1. 



Monstrilloida cyclopimorpha 



Remarks. The type of this section is the remarkable form described by 

 the present author in another place under the name of Thaumatopsyllus 

 paradoxus. The reception of this form within the division Monstrilloida 

 appears to be warranted by the above-mentioned general morphological character: 

 the total absence of both the posterior antennae and of any oral appendages. 

 Otherwise this form differs considerably from the Monstrilloid type. 



Fam. Thaumatopsyllidae. 



Remarks. As this family at present only comprises a single genus, it 

 may be sufficient to give the characters of that genus. 



Gen. Thaumatopsyllus, G. O. Sars, 1913. 



Generic Characters. Body of adult female cyclopoid in shape, the anterior 

 division being conspicuously dilated, the posterior slender and attenuated. Head 

 consolidated with the 1st trunkal segment, and having the front produced 

 below to a short and blunt rostral prominence. The 2 succeeding trunk- 

 segments normally developed, the 2 posterior ones, however, abruptly much 

 narrower and firmly connected with the tail, to form with it the posterior 

 movable portion of the body, Tail proper composed in female of only 3 

 segments, the last extremely slender and narrow, rod-like. Caudal rami well 



