tne Earhj SUujes of Piiltostoma schiiieri. 189 



are the same in number and arrangement, also its dorsal 

 spines, and tJie lateral processes are similar. The posterior 

 or anal portion has its margin entire, and four or five spines 

 on either side near the base ; the hind angles are obtuse and 

 rounded, and the hind margin forms a broad curve ; the 

 margin bears six long fine setse, on either side two arise con- 

 tiguously just under the margin immediately in front of the 

 angle, and one on the hind margin rather less than halfway 

 from the angle to the middle line ; they are very easily 

 broken ofl", hence one or more are frequently missing. 



The anal tuft consists of four very short branchial fila- 

 ments, sometimes ]).irtly hidden by the sucker. 



ISpiracles (PL IX. fig. 2, s.). — Tije second to ninth 

 pairs arc visible as black spots on the ventral surface, in 

 almost the same situations as those described and figured by 

 F. Miiller for his larva [op. cit. pp. 66-70, pi. vi. figs. 1-2). 

 There are two close together on either side of the ceplialo- 

 thoracic segment, a little within the base of the lateral 

 process. Each of the segments 2-6 bears a pair in front, 

 situated near the angles formed by the lateral margins where 

 these turn outwards to the bases of the lateral processes ; 

 these spiracles are often hidden by the outspreading branchial 

 fihunents. In addition to these, the sixth segment bears a 

 second and more conspicuous pair on its posterior (anal) 

 division, near the base, on either side of the sucker. 1 have 

 been unable to trace the first pair (whicli Miiller described 

 as being on the dorsal wall of tlie cephalothorax), unless the 

 •' eye-like spots " be they (see above, p. 187). Miiller found 

 the spiracles in his larva to be functionless, and connected 

 M ith the functional tracheal system by slender impervious 

 cords which he termed "' troncos iniciaes.'^ 



IV. The Pupa. (PI. X. fig. 5 ; PL IX. figs. 6-8.) 



Diagnosis. — Length ca. 3*5-4 mm. Dorsal surface bearing 

 numerous erect black setse, the arrangement of which is 

 described in detail below. Respiratory horns with the outer 

 laminaj triangular, with pointed apex. [Adhesive [)ads four 

 in numl)er on either side of the body iu all the material 

 before me.] 



The pupa is reddish or yellowish brown, rather shorily 

 and broadly ovoid, not very strongly convex. The segmenta- 

 tion is normal {cf Miiller, op. cit. pp. 75-79, pi. vii. fig. 4), 

 the metathorax and first two abdominal segments not reach- 

 ing the sides of the body, but being enclosed between the 

 mesothorax and third abdominal segment. The dorsal 

 surface bears very numerous erect black seta of varying 



