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BULLETIN OF THE BUREAU OF FISHERIES. 
Head one-half longer than wide, strongly flattened, widest through the bases of the antennae, which 
are attached near the anterior corners behind the bases of the mandibles. Sides of the head behind 
the eyes contracted in a uniform curve to a short neck at the posterior margin. Behind each group of 
eyes on the lateral margin is a tuft of silky hairs, and the curve from there to the neck is thickly set 
with short spines, nine or ten in number. At the center of the anterior margin on the dorsal surface 
is a short rounded rostrum, about one-quarter as wide as the head itself. The frontal border of this 
rostrum has a fringe made up of two rows of rigid flattened processes similar to those on the larva of 
Laccophilus maculosus. In the present larva, however, the difference in the lengths of the processes 
of the two rows is much greater, and in the ventral row of longer processes there are two lengths alter- 
nating with each other. The rostrum is strongly arched dorsally and is flanked on either side by a 
small projection tipped with three similar processes. 
The antennae are attached to the lateral margins behind the bases of the mandibles, are filiform 
and four-jointed, the terminal joint minute. The mandibles are slender, bluntly pointed, and grooved 
on the inner margin nearly to the base, which has a small tooth at its center on the dorsal surface. The 
maxillae have a short and narrow cylindrical cardo and a much wider stipes, whose tip is covered with 
short spines and whose inner margin is set with a dense fringe of short hairs, in the midst of which are 
two long curved spines or claws. The galea is a short finger like process tipped with a single seta; the 
palpifer is short, but the palp is long, filiform and three-jointed, the joints about the same length. The 
labium is short and twice as wide as long, its terminal margin armed with short, blunt, cylindrical 
processes. The labial palps are long and slender and two-jointed, the basal joint considerably longer 
and stouter than the terminal, though both are almost filiform. The ligula is wanting. 
The legs are long and slender, with a fringe of short hairs. Each tracheal gill of the abdomen con- 
tains a minute central tracheole, which is given off from the lateral trachea and is unbranched. From 
its dorsal wall a short tube leads to the spiracle in the same segment, which is inoperative during the 
larval stage. In the first segment the distance from the lateral trachea to the base of the spiracle tube 
is considerable, but this distance diminishes in each successive segment and becomes very short in the 
sixth segment. The spiracles on the seventh segment are ventral to the tracheae and are not visible 
in dorsal view. 
The general color of the fully matured larva is yellow with a light tinge of brown. On the dorsal 
surface of the head are two dark-brown spots, shaped together like the letter H, one on either side just 
in front of the eyes. Behind each group of eyes is an irregular spot extending backward and inward 
toward the mid line. The mandibles are brown, darker toward the tip; the center of the first joint of 
the antennae is slightly darker in color, while the center of the second joint is almost black; the ends 
of both joints are white. There is a dark-brown spot on either side of the neck at the base of the head, 
a ring of brown around each joint of the legs, and a narrow band at the base of the cerci, with a wider 
one at their tips. On the dorsal surface of each segment of the thorax and abdomen is a pair of sclerites 
faintly marked in brown; on the eighth and ninth segments these are fused and extend around the 
segment as in the Laccophilus larva. 
Pupation . — When fully grown, the larva crawls out on the land and burrows into the earth from 
three-quarters of an inch to an inch and a half below the surface. Here it hollows out a pupal chamber 
10 to 12 mm. in diameter, and after resting from 24 to 48 hours it pupates. As soon as it comes out of 
the water its spiracles begin to function and its lateral gills dry up and shrivel. Usually by the time 
pupation begins most of them are broken off, and the larval skins found inside of the pupal chambers 
seldom have more than one or two of them left still attached. 
Description of the pupa — General form ovate, not much widened anteriorly, rather bluntly rounded 
posteriorly. Total length, 6.75 mm. ; cerci, 2 mm. additional. Greatest width, at the second abdominal 
segment, 3 mm. Color brownish-white except the eyes, which are black. 
The head is sunken deeply in the prothorax and has a row of five small styli in front of, and another 
row of six behind each eye on the top of the head. The anterior and lateral margins of the pronotum 
are densely fringed with similar styli, and there are about eight along the posterior margin at each comer. 
The mesothorax and metathorax each have a group of five styli on either side of the mid line, and another 
group of three at the base of each elytron and wing. Each of the first seven abdominal segments has a 
group of from three to five styli on either side of the mid line and another group of two or three behind 
each spiracle. The eighth segment has two on either side of the mid line and one on each lateral margin. 
At the posterior end of the abdomen are the pupal cerci, which are very slender, 2 mm. in length 
and only one-seventh as wide at the base. 
