138 DR. T. THORELL ON SPIDERS FROM NEW [ Mar. 2, 
spines on the inner, and 1, 1, 1, 1 such spines on the outer side, all 
towards the apex; also the tibia has 1, | such spines on the inner 
side; with these exceptions the legs appear to be unarmed. The 
posterior part of the abdomen, from the anterior mamillee, is en- 
circled by closely set wrinkles ; the skin of its sides, in front of the 
mamillee, appears to be folded into closely set, elevated, longitudinal 
and somewhat undulated wrinkles. The vulva is a tolerably large, 
blackish, transverse area close by the rima genitalis: it is thrice as 
broad as long, and its lateral extremities are limited by a short 
inward curved costa: the anterior extremities of these two costz are 
united by another costa curved forward and forming with them 
almost a “—~>, and limiting two shallow foveee. The whole belly 
behind the rima genitalis is yellow. 
According to Keyserling, the legs of the fourth pair are the 
longest, and the first pair slightly longer than the second; and the 
thighs, patella, and tibice of both first and second pair of legs are 
armed with spines. His two specimens were from Mauritius. Dr. 
Vinson tells me that he has found in the isle of Réunion a second 
species of Arachnura, “ couleur jaune claire, jaune citron.” 
Is Arachnura really a goodgenus, different from Epeira, for instance? 
I believe it is so, and consider, with Vinson, its chief characteristic 
to be the long, transversely wrinkled or annulated flexible tail, into 
which its abdomen is drawn out behind: this tail, says Dr. Vinson, 
is “susceptible d’abaissement et d’élévation, et se recourbe égale- 
ment vers le dos ou vers le ventre.”’ 
Whether the Australian Spiders described by L. Koch under the 
names Epeira higginsii* aud HE. feredayi+ belong to Arachaura, is 
uncertain, as Dr. L. Koch does not state whether the tail in these 
Spiders is cross-ringed or -wrinkled, as in the typical species. To 
judge from his figures, the tail is destitute of such wrinkles; but if 
E. higginsii and E. feredayi should prove in this respect to resemble 
A. scorpionoides, I should not hesitate to refer them to Arachnura, 
even though their lateral eyes are separated by a smaller interval 
than in A. scorpionoides. The small difference in the relative 
lengths of the legs (1, 2, 4, 3, or 1, 4, 2, 3) does not appear to me 
to be a hindrance to our uniting them with Arachaura and removing 
them from Epeira, from which genus they differ in the absence of 
spines on the legs, also in this respect showing some resemblance 
to A. scorpionoides, which has spines only on the first pair (or first 
two pairs) of legs. 
LATHRODECTUs GEOMETRICUS, C. Koch. (Plate XXV. fig. 4.) 
Obscurius vel clarius nigro- vel rufescenti-fuscus, patellis et apice 
tibiarum late nigricantibus, cephalothorace fere dimidio breviore 
quam tibia primi paris, ordinibus oculorum extremitatibus non 
divaricantibus ; abdomine secundum dorsum annulis angulatis 
tribus et vitta postica undulata geminata albicantibus notato, 
in lateribus fasciis 3-4 obliquis geminatis albicantibus ornato, 
* Die Arachn, Australiens, p. 120, tab. xi. figs. 1-16. 
+ Ibid. p. 122, tab. xi. figs. 2, 2a. 
