ORTHOPORUS. TOL 
upon immature examples of the latter, especially since de Saussure’s words, ‘‘ Nous 
possédons 8 individus de cette espéce [O. otomitus], mais la plupart jeunes....,” 
leads to the inference that he had adult females of this species as he also had of 
O. montezume. 
Nothing is known about the pores of the fifth segment either in this species or in 
the following, O. fraternus. 
10. Orthoporus fraternus. 
Julus fraternus, Sauss. Mém. Soc. Phys. Genéve, xv. p. 374, t. 6. fig. 40 (1860) °. 
? Spirostreptus fraternus, Sauss. & Humb. Miss. Sci. Mex., Myr. p. 70 (1872) °. 
Closely allied to O. montezume, but smaller and more slender, with the antenne short and shaped as in 
O. otomitus, the third. fourth, and fifth segments being short. The ridges and grooves on the lower part 
of the anterior segments less pronounced than in O. montezume. Anal teryal plate so obtuse that it 
ceases to be terminated by an angle. 
Number of segments 75. 
Length 84 millim., width 4. 
flab. Mexico, Yautepec. 
This species was based upon a single female example. 
In 1872 de Saussure and Humbert doubtfully referred to O. fraternus a specimen 
from Mexico, but without definite locality, which had the anal tergal plate more 
angular and possessed only 63 segments. It was 66 millim. in length and 4 in 
width. 
11. Orthoporus confragosus. 
Spirostreptus confragosus, Karsch, Zeitschr. Ges. Naturw. (8) vi. p. 44 (1881)'. 
Spirostreptus (Scaphiostreptus) confragosus, Brélemann, Ann. Soc. Ent. France, lxxiv. p. 367, t. 9. 
fig. 20, and t. 10. fig. 21 (1905) ’. 
Colour brownish-black or olive-black, with the last segment and the ventral surface paler brown; the antennie 
and legs yellowish. First tergal plate with its postero-inferior angle widely convex and but little 
marked ; the anterior angle produced, more strongly so in the male than in the female, the margin above 
the angle slightly or more strongly concave; the inferior portion incurved and defined above by a ridge 
marked by the first groove, beneath which are many (6 or 8) longer and shorter grooves. Segments 
strongly suleate, the area behind the groove and immediately in front of it densely and deeply sculptured 
with punctuation and striole, the latter running for the most part longitudinally. Pores small, beginning 
on the sixth segment. Last segment finely shagreened and more coarsely sculptured than the preceding 
segment; tergal plate feebly angular, and valves with strong marginal depression. 
In the male the inferior angle of the mandible is somewhat strongly produced. ‘The copulatory apparatus is 
different from that of all the Central-American species in which this organ is known in that the distal 
portion of the anterior lamina of the coleopods is produced forwards into a thick roundish projection ; 
the posterior lamina bearing distally and externally a long, stout, bluntly-pointed process, projecting 
obliquely upwards and outwards from the inferior angle, which is not rounded, but geniculate and nearly 
rectangular. The peculiarity of the phallopod lies in the fact that the distal laminate enlargement is 
reduced to a narrow gutter leaving free a large part of the seminal style, which is stout and apically 
twisted. 
Number of segments 61-66. 
Length 78 millim. (¢) to 91(9), width 43 (3) to 5:8 (2). 
