401 



Page 230. 

 Add the following new genus : 



Gen. MalacOpSyllUS, d. 0. Sars, n. 



Generic Characters. Body slender cylindrical in form, with no sharp 

 demarcation between the anterior and posterior divisions. All integuments 

 remarkably thin and soft, partly clothed with delicate hairs. Rostral prominence 

 wholly obsolete. Caudal rami comparatively short. Anterior antennae slender 

 and narrow, 8-articulate, in male slightly hinged. Posterior antennae likewise 

 remarkably slender, with the basal joint not subdivided, outer ramus quite rudi- 

 mentary. Oral parts on the whole resembling in structure those in the genus 

 Stenocopia. 1st pair of legs very slender, with the inner ramus the longer and 

 only composed of 2 joints. The 3 succeeding pairs of legs likewise unusually 

 slender, with the 2nd basal joint produced outwards and forming with the 1st 

 an elbow-like bend; inner raraus much smaller than the outer, and composed of 

 only 2 joints, the proximal one very short; natatory setae of both rami considerably 

 reduced in number. Last pair of legs small, with the distal joint narrowly 

 exserted; proximal joint having outside a long and narrow process tipped with 

 a delicate bristle, its inner expansion very small. 



Remarks. This new genus differs from Stenocopia, to which it exhibits 

 a certain affinity, chiefly in the rudimentary condition of the outer ramus of the 

 posterior antennae, and in the rather different structure of the legs. The generic 

 name here proposed refers to the extremely thin and delicate integuments, which 

 give to the body a peculiarly soft and fragile consistency. Only a single species 

 of this genus has as yet come to my notice. 



Malacopsyllus fragilis, G. 0. Sars, n. sp. 



(Suppl. PI. 35). 



Specific Characters. Female. Body rather narrow, with the anterior 

 division slightly depressed, the posterior perfectly cylindrical. Cephalic segment 

 comparatively small, rounded quadrangular in outline, frontal margin perfectly 

 straight, without any trace of a rostral projection, lateral edges slightly curved, 

 and each exhibiting behind a knob-like prominence clothed with delicate hairs. 

 Lateral parts of the 4 succeeding segments rounded and likewise clothed with 

 delicate diverging hair-like bristles. Urosome about the length of the anterior 

 division and slightly narrower, with the posterior edges of the segments clothed 

 with delicate hairs ; last segment fully as large as the preceding one, and having 



