Carabideous Insects from the Straits of Magellan. 139 



ovatis, punctato-striatis, interstitiis paulo convexis. Long. corp. 



3^ lin. ; lat. If lin. 

 Hab. Tierra del Fuego. 



This species very closely resembles the M. ovalis, but the antennae 

 are longer and black at the base ; the thorax is more dilated in 

 front, and the elytra are rather more distinctly sculptured. The 

 most important difference, however, consists in the intermediate 

 tarsi of the male being distinctly dilated. In this respect the present 

 species resembles the M. Darwinii ; its smaller size, more elongated 

 form, more distinctly sculptured elytra, and the steel-blue colouring 

 of the upper parts, -w'AX serve to distinguish it. 



Sect. B, with the intermediate tarsi very indistinctly dilated in the males, 



Migadops ovalis, Plate III., fig. 3. — Mig. nigro-viridis ; corpore sub- 

 tus piceo ; antennis ad basin femoribusque piceo-rubris ; tibiis, tar- 

 sisque nigris ; capite lato, subdepresso, inter oculos foveis duabus 

 impresso ; thorace transverso, disco convexo, lateribus in medium 

 dilatatis, postice foveis duabus, atque punctis minutis, jmpresso j 

 elytris breviter ovatis, convexis, punctato-striatis. Long. corp. 

 3 lin. ; lat. If lin. 



Hah. Tierra del Fuego. 

 Head broad and depressed : thorax broader than long, moderately 

 convex above, the posterior angles acute ; the lateral margins some- 

 what reflected near the posterior angles, rounded, most dilated 

 in the middle ; the dorsal channel short, being generally confined to 

 the disc of the thorax ; behind, the thorax has a slightly marked 

 transverse impression, the area between which and the posterior 

 margin is very finely punctured ; on each side, towards the posterior 

 angle, is a largish and somewhat deep fovea. Elytra convex, and of a 

 short ovate form ; punctato-striated, the punctures distinct and rather 

 close together, but not large ; the interspaces of the strise flat, or very 

 slightly convex. The upper parts of the insect are of a greenish 

 black colour, sometimes inclining to blue-black, the under parts are 

 pitchy ; the basal joint of the antennae is pitchy red, the second and 

 two following joints are black, but more or less pitchy at the base, and 

 the remaining joints are dusky ; palpi black, the terminal joint pitchy 

 at the apex ; femora pitchy red ; tibiae and tarsi black, or pitchy 

 black. 



PI. III. fig. 3 a, labrum and mandibles ; 3 h, mentum ; 3 c, maxillae. 



This species Mr. Darwin found in considerable numbers at Kater's 

 Peak, Hermite Island, which is close to Cape Horn ; he also found 

 it on the mountains at Hardy Peninsula, in the month of February. 

 From the last-mentioned locality the specimens are of a larger size 

 (being 3| lines in length) than those found at Kater's Peak, but do 

 not appear to be specifically distinct. This insect is readily distin- 

 guished from other.s here described, if the males be examined, by the 

 two basal joints of the intermediate tarsi only being dilated in that 

 sex, and these joints are much less dilated than usual. The palpi 

 are moreover shorter. 



