1012 MR. OLDFIELD THOMAS ON THE [ Dee. 15, 
anterior side shortest, the posterior spots are largest; the fore 
half is bounded by a broadish lateral band of cream-colour, and 
from the inner extremities of the band a curved narrow tapering 
stripe of the same hue runs inwards and backwards, but their 
points do not meet; following this towards the spinners is a 
curved transverse cream-coloured stripe, being only linear in the 
middle, close behind which again is a short curved transverse 
cream line connecting the bases of two triangular patches of 
the same hue; spinners short, compact, underside dusky, 
margined with a cream-coloured suffused border. Colulus short, 
triangular. 
Received from Prof. Traill ; taken on the Amazons. 
EXPLANATION OF PLATE LII. 
Fig. 1. Aetius decollatus, 9 (p. 1007). 1a. Profile. 14. Eyes from above 
and behind. lc. Maxille, labium, and sternum. I1d. Sternum, 
showing more clearly posterior elongation and angular points. 
le. Genital aperture. 
. Friula wallaciti, 2 (p. 1009). 2a. Profile. 26. Abdomen from 
behind. 2c. Maxille, labium, and sternum. 2d. Lines showing 
natural length and width of Spider. 
3. Labdacus monastoides, G (p. 1009). 3a. Eyes. 36. Palpus. Se. 
Portion of palpus. 3d. Labium and fore part of sternum. 
4, Stephanopoides brasiliana, 3 (p. 1010). 4a. Eyes from above and 
behind. 40. Palpus. 
bo 
6. On the Genera of Rodents: an Attempt to bring up to 
Date the current Arrangement of the Order. By 
Oxp¥rieLp Tuomas, F.Z.S. 
[Received November 13, 1896.] 
Just over twenty years ago, in 1876", Mr. E. R. Alston con- 
tributed to this Society his invaluable paper ‘“‘ On the Classification 
of the Order Glires,” a paper which in its broad outlines has 
formed the basis for almost every Museum Catalogue, compiler’s 
list, and general text-book that has been written since it appeared. 
Based as it was on the earlier works of Waterhouse, Gervais, 
Brandt, and Lilljeborg, Alston’s arrangement has in this way 
received almost universal sanction, and the present writer is 
far from wishing to alter the essential characteristics of the 
scheme. 
But, owing partly to Alston’s not having seen examples of many 
of the genera included, and partly to the great increase in the 
number of known forms that has taken place since he wrote, his 
paper has gradually become somewhat obsolete in its detailed 
arrangement of the subfamilies and genera, however correct his 
positions for the suborders and families may still be considered 
to be. 
1 P.Z.8, 1876, p. 61. 
