AGABUS. 33 
tibiae: short and stout; all the tibie armed with more numerous spines than usual in 
the genus; the legs very little ciliate, the hind tarsi quite slender, the femoral cilia 
extremely rudimentary. The male has the front tarsi distinctly incrassate, the pubescent 
area of their under surface very small, and extending only to the second joint and the 
extremity of the first ; the middle tarsi are rather longer than in the female, and their 
basal joints are a little incrassate, the first joint with a small pubescent area beneath ; 
in this sex the posterior femur has a very obscure angle on the hind margin near the 
base. In each sex the apical ventral segment is entirely destitute of ruge, and has 
only three or four punctures on each side. The female has a distinct reticulation on 
the head and thorax, which appears to be more obsolete in the male. 
2. Agabus americanus. (Tab. I. fig. 8.) 
Agabus americanus, Aubé, Spec. Gén. vi. p. 334; Sharp, Trans. Roy. Dubl. Soc. n. s. li. p. 498. 
Hab. Mexico, Las Vigas, Cerro de Plumas (Hége), Parada (Boucard, coll. Sallé). 
_ This seems to be a rather variable species. There are two forms of the female among 
the specimens before me: this sex is usually very polished and shining like the male; 
but there are two or three individuals in which the thorax and elytra are very densely 
strigose-reticulate and quite dull, the extremity of the wing-cases, however, like the 
head, being shining and without strigosities. 
The position of the species is very difficult to decide; but I think that it should 
probably be isolated as a group to be located near groups 2 and 5 of my memoir. 
3. Agabus amaroides. 
Oblongo-ovalis, parum convexus, niger, supra nigro-eneus, antennis rufis, pedibus piceis ; superne vel nitidus 
obsoleteque reticulatus (¢ ), vel subopacus conspicue densissimeque reticulatus ( @ ); prothorace elytris 
paulo angustiore, lateribus obliquis parum curvatis, angulis posterioribus rectis, haud rotundatis. 
Long. 4-44, lat. 23 lin. 
Hab. Muxico, Las Vigas (Hége). 
The prosternal process is rather broad and finely margined, nearly flat. The hind 
coxee are rather small, and are finely but distinctly and densely strigose. The hind legs 
are slender, the tarsal claws large, the femoral cilia moderately well developed. The 
male has the three basal joints of the front and middle tarsi a good deal incrassate, and 
furnishing beneath a large area covered with rather long glandular pubescence ; the 
anterior claw of the front foot has the basal portion dilated, so as to form a large lobe 
with acute angle; in this sex the apical ventral segment is coarsely longitudinally 
rugose. In the few individuals before me the difference in sculpture of the sexes is 
remarkable. One of the two males has a remarkable monstrous development of the 
left anterior tarsus, it being provided with no less than six claws; these claws are placed 
so as to form three pairs, of which the anterior and posterior pairs, may be described 
BIOL. CENTR.-AMER., Coleopt., Vol. I. Pt. 2, Aprid 1882. FF 
