WHITTLEIA RETIELLA. 343 



rounded blades of Sclerachloa (Poa) maritima. They are not laid on 

 straight as in Fumea, nor do they lie quite close like the grass blades on 

 the case of E. pulla, still they follow the curve of the case, especially 

 approximating at the free end, so that the case is like that of E. pulla, a 

 little spindle-shaped, and the unattached end usually flattened, so as to 

 have two flat sides and two edges, on one flat side two or three pieces of 

 grass project beyond the end of the case, but so closely together as to 

 look like one piece. These project from half as long to quite as long 

 as the case itself. There is a good deal of muddy-looking material 

 between the straws, and there is, as usual, a flexible mouthpiece covered 

 with smaller chips (Chapman). The case is made of fine grey silk, is 

 about 9mm. -10mm. long, with six or eight slender grass stems 

 attached longitudinally to the outside, three of these, on dorsal area, 

 project beyond the end of the case. A coating of dried mud and small 

 particles of earth is noticeable on the silk between the straws (Bacot). 

 The case is soft, slender, close fitting, hardly cylindrical, but curved in 

 a little at the ends, composed of silk, mixed with morsels of Conferva, 

 and partially covered with short bits of very slender dead grass, which 

 look half decayed, and are dotted over with the confervoid matter so 

 plentiful in salt marshes. The case has been found on Artemisia mari- 

 tima, in salt marshes, but there is no doubt that it is usually concealed 

 low down among the tangled mass of Spartina stricta, with which the 

 drier portions are often covered (Barrett). Chapman notes that when 

 fixed up for pupation the case is generally attached to a grass stem, 

 often high up and at an angle of about 45°, that it is found among 

 Sclerochloa maritima (not Spartina stricta), and often occurs where no 

 Conferva is to be found. 



Larva. — The head large, thoracic segments small, compared with 

 the larvae of Fumea. Head slightly retractile ; meso- and metathorax 

 not much larger than prothorax, the metathorax the shorter. The abdo- 

 men very large and bulky compared with thorax (probably a ? larva). 

 Head and chitinous parts of thoracic segments black with polished 

 surface ; the metathorax does not seem so horny and completely 

 covered with chitin as in many other larvae examined. A white, 

 mediodorsal stripe commences on prothorax, widening gradually to 

 metathorax. A less defined lateral stripe is also present ; the anterior 

 margins of the thoracic segments and intersegmental areas whitish or 

 flesh-coloured ; the abdomen pale brownish or drab in colour with a 

 faintly marked mediodorsal line. The anterior abdominal segments 

 are both less in girth and in width than the posterior, the 6th and 7th 

 abdominals being the largest. The abdominal segments are composed 

 of two subsegments, but the divisions are not distinct on the posterior 

 segments — 6th and succeeding ones ; the anal segment bears a 

 black polished dorsal plate. The hairs are fine and tapering, long 

 on thoracic segments and head, short, weak, and tending to become 

 atrophied on all the abdominal segments except the 10th. The 

 tubercles are single-haired, with spreading chitinous bases on the 

 abdominal segments, this character being especially noticeable in the 

 dorsal tubercles on the 1st, 2nd and 3rd abdominal segments. The 

 tubercles are arranged as follows : i andii dorsally as trapezoidal tubercles, 

 i outside of and weaker and smaller than ii ; iii is supraspiracular, and 

 well-developed ; iv and v are subspiracular, placed close together, and 

 weak, especially v ; another (vi) is placed below the lateral flange, 



