ZooL.— Vol. II.] COLEMAN— DACTYLOPIUS SEQUOIM. 411 



is so closely associated with the eighth that it cannot be 

 clearly distinguished. In specimens which subsequently 

 develop into males, the lateral margins of each segment are 

 furnished with a few slender spines, visible only under the 

 high power of the microscope. These spines are not present 

 in the female at any stage. There are about six short hairs, 

 or spines, between the eyes, three on either side of the 

 middle point. From either margin of the eighth abdominal 

 segment there arises a conical protuberance, bearing a 

 single long hair and two short ones about one-third the 

 length of the long one. The caudo-ventral margin of the 

 ninth segment bears the anal ring, a narrow, flattened, cir- 

 cular ring-plate, bearing the six slender, equidistant hairs, 

 which are about .06 mm. in length. Protruding from this 

 ring may be noticed a conical organ supposed to be the 

 anus. The outer lobes of the ninth segment bend around 

 until they are nearly on a level with the end of this organ. 



The two eyes are situated on the cephalo-lateral angles 

 of the head, and rather below the lateral line. They are 

 not very prominent and show no dark pigment as in some 

 other species. The mouth-parts are similar to those of 

 the adult female, except that the buccal set^ are quite 

 long, so that when doubled up in the body they reach to the 

 last abdominal segment. The labium, or beak, is also large 

 in proportion to the other parts. 



The antennae arise from the cephalo-lateral angles of the 

 head, just in front of the eyes. They are about .15 mm. 

 in length, of quite regular outline, and six-jointed. The 

 formula is 6, 2, (3, 4, 5) i; i- e., the sixth segment longest, 

 the second next in length, segments three, four, and five 

 about the same, and segment one the shortest. The antennas 

 are well supplied with hairs, the figure (fig. i) showing 

 their distribution. 



The legs are nearly equal in size and shape, so that a 

 description of one will answer practically for all. The coxa 

 is quite large, rather broad at the base. The trochanter is 

 also large, its angle being somewhat more than a right angle. 

 The femur is longer and broader than any other segment. 



