682 GEOLOGICAL SURVEY OF THE TERRITORIES 



EXPLANATION OF PLATE XXXIV. 



Fig. 1. Streptocephalustexanns'Pack. Third, developmental stage, dorsal view. Length 



0.2™™, oc, ocellus; md, mandibles; mo!p, mandibular palpus; sgf, shell gland ; 



m, transverse muscle of the 2d antennse ; m^, levator muscle of the labrum ; 



m*, rectal muscles ; int, intestines ; s', forked spine on 2d joint of 2d anten- 

 nae. 

 Fig. la. Union of the tAvo muscles m' in Fig. 1. 

 Fig. 2. 2d antennae seen from below. Larva 4.2™'° in length. 

 Fig. 3. 1st antennss, 3d larval stage; n, antennal nerve; mnc, marginal nerve-cella; 



sp. c, bipolar spindle-shaped cells ; s, setae. 

 Fig. 4. 1st antennas of larva when 3™™ in length; lettering as in Fig. 3; gc, terminal 



ganglion cells. 

 Fig. 5. 2d antennae of larva 4™™ in length; s^, s*, spines of basal joints. 

 Fig. 6. Mouthparts of same larva as Fig. 5, and drawn to the same proportions ; md, 



mandible; mp, mandibular palpus; mx^, 1st maxilla; m'p, 1st maxillary 



palpus ; vix"^, 2d it- axilla. 

 Fig. 7. The maxillae (1st and 2d) of larva when i")™™ in length. 

 Fig. 8. Chirocephalus holviani Ryder (Glendale, L. L), tip of lat antennae and olfactory 



seta. 

 Fig. 9. Mouth of larva of S. texanus when .5™™ in length. 

 Fig. 10. BrancMpus vernalis Verrill. Olfactory seta. 

 Fig. 11. Chirocephalus holmani Ryder. Dorsal bristle of 3d segment, a little way from 



the articulation ; Fig. 11a, the same on the 2d (genital) segment. 

 Xote, — All the figures in this plate were dT.awn by C. F. Gissler, Ph. D. 



