508 STAPHYLINIDA. 
have the thorax and the tibiz and tarsi darker in colour, and the abdominal lobe of the 
male rather more slender, and the setigerous impressions on the third and fourth 
segments rather less extensive. The examples from the State of Panama are all very 
aberrant. There are two males and one female from Bugaba; all are of small size, and 
the males have no trace of the abdominal lobe; the setigerous impression of the third 
segment is not extensive, and that on the fourth segment assumes the form of a rather 
small elliptical space: the two examples from San Feliz are males, and have the hind 
body pale, which is probably the result of immaturity, and the sexual characters similar 
to the Bugaba examples, except that the setigerous impressions are of rather larger 
size. I cannot look on these differences as specific; whether they are examples of local 
or endemic sexual variation remains to be tested by examination of a larger number of 
specimens. 
Solsky has merely recorded the supposed occurrence of C. ruficolle, Motsch., in our 
region ; but I feel sure the determination was erroneous, and that the true C. rujicolle 
does not occur in Mexico; and I also suppose it not improbable that C. collare was the 
species Solsky alluded to. 
We have figured a well-developed male from Oaxaca. 
2. Cryptobium umbratum. 
Sat latum, nigricans; antennis pedibusque piceis, femoribus rufis ; capite sat elongato, quam elytra vix latiore, 
crebrius fortiter punctato; prothorace crebrius fortiter punctato, medio longitudinaliter levigato; elytris 
quam thorax paulo longioribus, crebrius fortiter punctatis ; abdomine subtiliter punctato. 
Long. 12 millim. 
Hab. GUATEMALA, near the city, San Joaquin, and Balheu in Vera Paz (Champion). 
This species is very closely allied to C. collare, but differs as follows:—it is of more 
slender form and of darker colour, the head is rather more deeply punctate, and not so 
dull, the elytra are a little shorter and not quite so densely punctate, and the hind body is 
rather more closely and finely punctate, and the sexual characters are different; in the 
male the fourth ventral segment bears a very broad lobe, which does not get narrower 
behind ; its margins are fringed with very long hair, the hind margin being rounded; 
at the base of the same segment there is a large circular setigerous fovea, and on the 
preceding segment a transverse setigerous line. In the female there are no abdominal 
fovee. The male characters vary greatly in their development; the description above 
gives them as seen in well-developed examples, but in some cases the lobe is reduced 
to a quite short, broad projection, and the setigerous impressions to mere punctiform 
fovee. 
A good series was obtained of this species. Specimens of this and other species of 
the genus were captured by Mr. Champion on the sandy banks of small streams at the 
bottoms of the very deep ravines or “ barrancas” near the city of Guatemala. 
