216 
HISTORY OF BRITISH CRUSTACEA. 
Firth of Forth (Goodsir) ; Strangford Lough (Hyndman 
and Thompson) . 
Gaprella acutifrons. Leach’s Skeleton Screw . — Head 
oval, surmounted by a point ; lower antennae much ciliated; 
first joint of thorax cylindrical, not thicker than the head. 
British coast. 
Gaprella phasma. Montagu’s Skeleton Screw . — Head 
round, surmounted by a point ; first joint of thorax nar- 
rowed behind, armed with two strong spines one before the 
other. 
South of Devon (Montagu) ; Isle of Man (Dr. Fleming). 
Colonel Montagu, in the ‘Lirmean Transactions/* records 
his observations on the Caprella phasma . He remarks that 
“the female differs in possessing several plates or valves 
beneath the body, situated between the two pairs of fins; 
the office of these is to carry and protect its eggs or young, 
at which time they extend very considerably, and form a 
kind of pouch. We have seen this receptacle distended 
with ova, from fifteen to twenty, readily distinguished through 
the transparent plates. In this part a very strong pulsation 
is observable. 
“While examining a female in a watch-glass of sea- water 
* Yol. vii. p. 67. 
