156 DIPLOPODA. 
visible on the 13th and increasing in size to the 18th, where it is very marked; the anterior angle 
forming a continuous curve with the anterior border, which is serrulate from about the 10th, posterior 
angle acute and becoming gradually more and more produced and spiniform to the 13th—16th, on which 
it is slightly hooked inwards. On the 17th the spiniform process is short; on the 18th and 19th it is 
absent, the posterior angle of their keels being blunt. Lateral border of the poreless segments straight ; 
of the pore-bearing segments deeply notched just in front of the pore; pores becoming posteriorly 
gradually more and more visible from the dorsal side; on the 18th, and especially on the 19th, they 
are on the upper side, and on the 19th quite recall the position of the pores in some species of Platy- 
rhacus. Posterior border of the keels weakly serrulate. Caudal process wide, with parallel sides and 
sharply rectangular angles, the posterior border being transverse, straight, not lobulate, and without 
visible setae. Yerminal segment of legs bearing short slender spines. 
Length (minus head and segments 1-5) 75 millim., width 15. 
Hab. Guatemata (Stoll). 
This species, both in size and general characters, is nearly allied to P. heterosculptus 
of Carl, but differs in having all the segments uniformly rugose and covered with 
granulation, the 19th granular throughout, the coarser tubercles much less numerous 
and less distinct, the greater part of the keels yellow, and the anterior border of the 
keels more prominent basally, more convex, and the posterior border less concave and 
with a basal shoulder-prominence, at least in the posterior part of the body. According 
to Carl, the median area of the back in P. heterosculptus is smooth, or at all events much 
smoother than the sides, so that the polygonal areas are distinctly exposed; the larger 
tubercles are very numerous and arranged in about five irregular rows, the polygonal 
areas being also more numerous; the 19th segment is only rugose behind; the dorsal 
area is said to be brown, without any mention of yellow on the keels; and, lastly, on 
the 16th segment the posterior border is evenly and somewhat strongly concave, and 
there appears to be no basal shoulder-prominence on the posterior border of any 
of the keels. 
8. Polylepiscus furcifer, sp.n. (Tab. XII. figg. 1-1 h.) 
Colour brown, with the greater part of the keels and the caudal process yellow ; antenne and legs brownish. 
Dorsal surface showing distinet sculpturing, polygonal areas arranged mostly in three transverse rows, 
which on the posterior segments break up into more numerous less regularly arranged rows; the areas not 
covered with fine granulation as in P. actewon, but each of them, at least on the median segments of the 
body, bearing a central tubercle; these tubercles more distinct and more constant in occurrence upon 
the lateral slope of the dorsal area and upon the upper side of the keels, showing a strong tendency to 
complete obliteration in the middle of the dorsal surface ; on the upper side of the keels the polygonal 
_ areas are for the most part lost in the strigose sculpturing ; both tubercles and areas more numerous on 
the posterior segments ; on the anterior segments the median area is nearly smooth, the lateral portion 
showing weakly defined polygonal areas and tubercles. First teryal plate nearly smooth, weakly 
sculptured laterally, its angles only a little produced. eels of succeeding segments much like those of 
P. stolli and P. aciwon, the lateral margin being thickened and notched on the pore-bearing segments, 
and almost straight on the poreless segments; the posterior angle is acute and becomes gradually more 
and more produced and spiniform back to about the 16th; anterior border of keels produced slightly 
forwards; the posterior border slightly shouldered basally in the posterior half of the body, and distinctly 
serrulate, the serrulation extending even on to the spiniform processes. Pores almost wholly lateral, 
even on the 19th, where they are scarcely visible from the dorsal side; this segment markedly granular 
