ON DEVELOPMENT OF ATYEPHIRA COMPRESSA. 419 
rest, and shows two lobes plainly. These lobes indicate the 
future csecal ends, (fig. 79, ce .) situated above the pyloric 
division of the alimentary canal. 
The first pair of antennae (fig. 80, At. 1.) becomes two-jointed, 
bearing four setae at its extremity. The endopodite has not 
yet appeared. 
In the second pair of antennae (fig. 80, At. 2), the setae of 
the exopodite {At. 2, ex.) have much increased both in size 
and number. From the internal branch two long setae become 
visible. 
The mandible is now a bilobed appendage ; the anterior lobe, 
which is larger, shows two rows of about seven teeth. A small 
moveable appendage (endopodite?), beset with minute setae on 
its border, is seen at the end of this lobe. 
Both lobes of the first pair of maxillae (fig. 81) have a number 
of setae on the ends. The inner side of the inner lobe shows 
about five lobules beset with setae. 
The second pair of maxillae (fig. 82) is little smaller than the 
first pair, and is furnished with numerous setae on its inner 
lobe, which is cut into five lobules. 
The first, second, and the third pairs of maxillipedes (fig. 83) 
have not undergone much change. They are, however, all 
provided with setae on their extremities. 
Behind the maxillipedes the first pair of ambulatory legs 
(fig. 83, amb. 1) becomes visible as a simple bilobed appendage. 
The dorsal spine is lost. 
About twenty-four hours afterwards the mandible and the 
maxillae (fig. 84, md., mx. 1, 2) have undergone great changes. 
The scaphognathite (fig. 84, mx. 2, s. g) of the second pair of 
maxillae is seen in rapid motion. The pigment patches now 
appear at different parts of the body. Their distribution is 
almost similar to the first stage after hatching. 
Embryo just hatched (fig. 85). — About twelve hours after 
the stage last described the embryo is hatched. It measures 
about 3j mm. in length. The carapace is broad, produced 
between the eye into a rostrum ( rs .), at the base of which is a 
simple median eye {ocl.). The compound eyes (oc.) are large, 
