216 BOPYRIDZ. 
breadth to its extremity, which is rounded, the six 
segments of which it is composed having the lateral 
margins thinner than those of the body; on the upper 
side the articulations are almost obliterated, whilst its 
lower surface is covered with five pairs of pleopoda, each 
consisting of a single membranous plate of a somewhat 
triangular form, the terminal segment being destitute of 
any lateral appendage. 
The genus Bopyrus was established by Latreille in one 
of his earliest works, and was placed by him amongst the 
Isopodous crustaceans, being, in the first edition of the 
“ Réene Animal,” placed at the end of the order, 
with the view of showing what might be regarded 
as its organic degradation as compared with the other 
animals of the order. In the second edition of the same 
work, however, Latreille placed the genus at the begin- 
ning of the order, in a section termed Epicarides, with the 
view of bringing it into close connection with the Cymo- 
thoades, with which it has an evident affinity. 
In 1772, M. Fougeroux de Bondaroy published a 
memoir on B. squillarum,* in which he completely dis- 
proved the old fallacy entertained by fishermen on the 
coasts of France, that the Bopyri were the young of 
soles or other flat fish which took shelter under the 
shell of the prawn to protect them in the early state of 
their existence—an idea which even Deslandes had held 
and recorded in the Mémoires de l’Académie Royale des 
Sciences de Paris in 1772. 
In 1837 some interesting observations upon the genus 
were published by Heinrich Rathke, “De Bopyro et 
Nereide. Rige et Dorpati,” 4to; also in his work 
on morphology, ‘‘ Reisebemerkungen aus Tamien.” 
* Hist. de l’Acad. des Sciences, 1772, p. 29, t. 1. 
