EUTYPORHACHIS. 169 
notch which separates it from the thickened but not prominent porous area. ‘The 
upper surface is granular and rugulose. Until this species has been rediscovered and 
the character of the male made known, the position of Odontopeltis will remain 
unsettled. It may be that none of the forms referred to Odontopeltis by Attems and 
myself are congeneric with R. conspersus. At all events, it appears to me to be 
practically certain that the one I have described below as ELutyporhachis tessellatus is 
generically distinct from it. 
The two species here referred to the genus Hutyporhachis may be distinguished as 
follows :— 
Posterior area of terga behind the transverse groove tessellated, the anterior shorter 
areas irregularly rounded, the posterior larger, longitudinally oblong, scarcely 
tubercular; the single subsidiary branch of phallopod not much expanded 
proximally, strongly bigeniculate. 2. 2... 2 1 ew . . .  tessellatus. 
Sculpturing of posterior area of terga behind the sulcus tubercular, the tubercles of 
the posterior row overlapping the edge of the segments; phallopod with two 
subsidiary branches, the larger forming a funnel-sbaped expansion on the inner 
side of the seminal stile and not bigeniculate. . 2. . . 0. . 2...) Ooltramarei. 
1. Eutyporhachis tessellatus, sp. 0. (Lab. XIII. figg. 4-4 ¢.) 
3. Colour piceous above; the pore-bearing area of the keels sometimes paler; legs and antenne yellowish 
brown. Antenne long, not incrassate, the second segment only a little longer than the third, fourth, 
fifth, and sixth. Head smooth above, hairy below; frontal sulcus distinct. Body as wide anteriorly 
as in the middle, attenuated posteriorly ; keels widely separated. rst tergal plate smooth above, lightly 
convex; its anterior border not quite evenly curved, being straightish across the middle, laterally strongly 
convex, with well-developed posteriorly acutely pointed angle projecting backwards as far as the posterior 
border of the median area, with the intervening posterior border of the keel somewhat strongly concave. 
All the keels high on the sides, projecting horizontally, so that the back is nearly flat; their anterior 
border convex and becoming gradually more and more sloped backwards from the 2nd to the 19th 
segment, forming an even arch with the anterior half of the lateral border, so that from the 4th 
backwards no definite anterior angle is formed; the posterior angle acutely produced on all the keels 
and surpassing more or less the posterior edge of the median portion of the tergal area; those of 
the 2nd, 3rd, and 4th with posterior border more concave and angle more produced than are those 
of the median area of the body, where the posterior border is sometimes lightly convex or inclined 
forwards, then abruptly bent backwards, sometimes showing a few small teeth, which, however, are 
inconstant; from the 16th to the 19th, where the body is narrowed, the keels become gradually produced 
more and more backwards, those of the 18th forming strong spiniform processes, those of the 19th 
smaller spiniform processes; antero-lateral edge of the keel elevated, on the poreless segments, the 
elevated edge gradually passing into the thickening which pervades the posterior angle; but on the pore- 
bearing segment the pore-area is more abruptly and more strongly thickened, and is defined from the 
anterior portion of the lateral border by a distinct notch, except on segments 17 to 19. Dorsal area 
strongly sculptured, as in the genus Po/ydesmus ; each metazonite marked with a deep, central, mesially 
angled transverse sulcus ; the area in front of this smooth, but mesially suleate, and furnished usually 
with two pairs of small setigerous granules; the area behind the sulcus divided up into two transverse 
rows of low polygonal areas which are posteriorly weakly tuberculiferous, the areas of the anterior row, 
usually six in number, shorter than those of the posterior row, which are usually eight in number 
and longitudinally suboblong ; sometimes the areas of these two rows almost fuse, and externally 
they pass into a few similar but less well-defined areas upon the upper side of the keels ; the 2nd and 3rd 
BIOL. CENTR.-AMER., Diplop., December 1909. Z 
