MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 59 
facets, aud not depressed. Antennae rather long, the joints subclavate, joint 6 not much longer than 4; joints 3 and 
5 of the same length ; joint 6 rather thick at the end; joint 7 short, thick, and conical, much more so than usual. 
Body segments swollen .and full, becoming suddenly depressed on the front edge; the swollen portion with 
numerous raised lines or ridges, with deep concave valleys between; the ridges projecting behind in an acute point. 
The segment next to the head rather narrower than the head, with the posterior two-thirds ridged; the sides of the 
segments are somewhat swollen high up on the sides, but not so conspicuously as in Pseudotremia. Legs rather 
stout and larger than in Pseudotremia; the first pair rather short and broad, with a regular comb of stiff set® on 
the inner edge of the terminal joint. The seventh and ninth pairs of legs, i. e., the pair immediately preceding and 
following the genital armor, are like the others, not being in any way modified, as in Pseudotremia, etc. The 
genital armature is large and better developed than in any other genus of the family; the outer lamina large, 
stout, spatulate-mueronate at the tip; inner lamina much shorter than the outer, and with two long acute forks; 
repugnatorial pores difficult to find. 
The genus may be recognized by the long, slender body, tapering to a point, and by the very short conical sev¬ 
enth antennal joint; by the ribbed, swollen segments, which are very numerous ; by the seventh and ninth pairs of 
legs being normal, like the others; and by the short, broad first pair, with the regular comb of set® on the terminal 
joint. 
The genus as here defined will apply to the two southern European species Lysiopetalum carinatum Brandt and 
L. illyricum Latzel, except that they are setose, while our species is not. I am indebted to Dr. Latzel for specimens 
for comparison. 
In proposing the genus Spirostrephon, Brandt (Bull. Sci. Acad., St. Petersb., 1840) regarded Say’s Julus lactarius 
as the type species, and adding that the eyes are in a triangular area, he indicates its generic difference from Cambala 
annuiatus, with which it has been so often confounded. 
Although I had originally retained Brandt’s name Spirostrephon for our species, yet upon receiving from Dr. 
Latzel authentic types of European Lysiopetalum, it is plain that our S. lactarius is congeneric with them. The 
name Spirostrephon should, then, be considered as a synonym of Lysiopetalum. It is difficult to see why Brandt 
should have separated lactarius from his L. carinatum. 
In his Eecueil, page 42, Brandt thus characterizes his genus Lysiopetalum: “ Lamin® pedifer® omnes liber®, 
mobiles, cutis ope cum parte abdominali corporis cingulorum conjunct®. Erons ante antennas dilatata et deplanata 
in maribus in simul depressa.” The two species mentioned under the generic diagnosis are Lysiopetalum fcetidissimum 
(Savi) and L. carinatum Brandt. 
Again, on page 90: “Subgenus seu genus II, Spirostrephon Nob.” is thus characterized, and he apparently regards 
it as a subgenus of Julus: “Gnathochilarii pars media fossa baud instructa, sede jus loco aream tetragonam planam, 
plica seu linea derata duplici, superiore breviore et inferiors longiore, supra et infra terminatam, sed sutura longi- 
tudinali baud divisam offerens. Spec. 27. Julus (Spirostrephon) lactarius Nob.Differt habitu a Julis genuinis 
et Julo (Lysiopetalo) fmtidissimo et plicato affinis apparet. Annuli corporis, quorum posteriores brevissimi, incluso 
anali 53. Pedum paria 95. Longitudo 10 to ll m ; latitude smiraia f 111 . Qculi triangulares— Julum lactarium protypo 
generis Cambala Grayi habuissem, qunm figura ab hocce zoologo sub nomine Canibalas lactarii data” (Griffith Anim. 
Kiugd. Insect., PI. 135, fig. 2). The generic characters are not very applicable in distinguishing the genus, the men¬ 
tion of the type alone rendering it possible to understand what the genus is. 
The synonym will be further discussed under Cambala. In 1844 Newport, having been misled by the specimen 
of Cambala annulata alleged to have been sent by Say as the type of his Julus lactarius, places the latter in his genus 
Platops, which he proposes, with a doubt, thus: “Genus Platops? mihi.” The generic characters apply well to the 
present species, S. lactarius. 
Dr. Wood, in his Myriopoda of North America, does not attempt, for want of material, to define the genus. 
Professor Cope characterizes this and the next genus thus: 
Annuli without pores... Spirostrephon. 
Annuli with two pores on each side the median line.. Pseudotremia. 
As we have seen, there are pores in Lysiopetalum, while the “ two pores ” of Pseudotremia are two of the three 
setiferous tubercles on the side of each segment. 
The genus appears thus far to be represented in North America by but a single species, which ranges from Mas¬ 
sachusetts west to Iowa and south to Florida and Louisiana, while in southeastern Europe Lysiopetalum is rich in 
species. 
Lysiopetalum lactarium Say. Plate IX, figs. 3, 3a~3h. 
Julus lactarius Say, Journ. Acad. Nat. Sci., Phil., ii, pt. i, 104, 1821. 
Spirostrephon lactarius Brandt, Bull. Sci. St. Petersb., 1840. Recueil, 90, 1840. 
Platops lineata Newport, Ann. Mag. Nat. Hist., xiii, 267, April, 1844. 
Lysiopetalum lineatum Gervais, Aptferes, iv, 133, 1847. 
Cambala lactarius Gervais (in part), Apleres, iv, 134, 1847. 
Beasia spinosa Sager, Proc. Acad. Nat. Sci. Phil., 109, 1856. 
Cambala laciaria Gervais, Exped. l’Amer. du Sud (Castelneau), Myriop., 17. 
“Beana chinosa Saeger,” Gervais, Exped. l’Amer. du Sud (Castelneau), Myriop., 14. 
Spirostrephon lactarius Wood, Myriop. N. Amer., Trans. Amer. Phil. Soc., Phil., PI. ii, figs. 11, 11a, 192, 1865. 
