THE ANNALS 
AND 
MAGAZINE OF NATURAL HISTORY. 
[FIFTH SERIES.] 
No. 44. AUGUST 1881. 
VII.—On the perfect State of Prosopistoma punctifrons. 
By M. ALBERT VAYSSIERE*. 
[Plate X.] 
THE curious Arthropod that is the subject of this memoir was 
left, until within the last few years, in the class Crustacea, 
although its principal characters ought to have led to its being 
referred to that of Insects. It is, indeed, to this uncertainty 
as to its systematic position that it owes a part of the interest 
it has aroused. 
From the extreme rarity of this animal the naturalists who 
had to refer to it have not always been able to verity the asser- 
tions of their predecessors. ‘This insect was observed and 
figured for the first time in 1800, by Geoffroy, under the de- 
nomination of Binocle @ queue en plumet, then by Latreille, who 
indicated it under the name of Binocle pennigére, and lastly 
by Duméril, who gave it the denomination of Prosopistoma, 
atter having first of all called it Binocle pisciforme. A little 
later the learned Dean of the Sorbonne, M. H. Milne-Hd- 
wards, mentioned it at the end of his ‘ Histoire des Crustacés,’ 
* Translated by W.S. Dallas, F'.L.S., from the ‘ Annales des Sciences 
Naturelles,’ 6° sér. tome xi. (1881), pp. 1-16. 
Ann. & Mag. N. Hist. Ser. 5. Vol. viii. 6 
