528 



THYSANOPTERA 



(Fig. 254) found on the left side of the body, as probably an enor- 

 mous development of the epipharynx. Previous to the appearance 



of Uzel's work, G-arman had, however, 

 correctly described the structure of the 

 mouth; 1 he puts a different interpretation 

 on the parts; he points out that the 

 mandibles (/), so-called by Uzel, are at- 

 tached to the maxillae, and he considers 

 that they are really jointed, and that 

 they are lobes thereof; while the Mund- 

 -T> stachel or piercer is, he considers, the 

 left mandible ; the corresponding struc- 

 ture of the other side being nearly 

 entirely absent. He points out that 

 the labrum and endocranium are also 

 asymmetrical. We think Garman's 

 view a reasonable one, and may re- 

 mark that dissimilarity of the man- 

 dibles of the two sides is usual in 



FIG. 254. Face (with base of T n ,-, ,, -,., ! 



the antennae) of Aeoiothrips Insects, and that the mandibles may 

 fasdata. (After Uzel.) a, b e hollow for sucking, as is shown by 



Labrum ; b, maxilla with its . . ., T _ .. .. .. 



palp (c) ; bi, terminal part of the larvae ot Hemerobudes. There 

 vertex near attachment of are usually three ocelli, but they are 



mouth-parts ; a, membrane . * 



between maxilla and mentum ; absent in the entirely apterous forms. 



e, mentum ending in a point The wi g appear to spr i n g f rom 



near /, g, membrane of ** 



attachment of the labial palp the dorsal surface of the body, not 



h ; i, ligula ; j, j the bristle- f rnrn 4-V. p eirlpcj HIP ant prior nair i<s 

 like mandibles ; k, the thicker * ^ ' 



base of mandible ; i, chitin- always quite separated from the pos- 



S/uftiiS iSSSft terior ' the win s are hn i* slender ' 



and o, its connection with sometimes very slender ; in other re- 



the forehead, r, r; p, for- ,., ., . -, , , . , 



amen of muscle; s and t, spects they exhibit considerable variety ; 

 points of infolding of vertex ; sometimes the front pair are different 



u, a prolongation of the . , , . . _ 



in colour and consistence irom the 



-if 



other pair. The abdomen has ten seg- 



ments, the last of which is often tubular in form. The peculiar 

 vesicular structures by which the feet are terminated are, during 

 movement, alternately distended and emptied, and have two hooks 

 or claws on the sides. The stigmata are extremely peculiar, 

 there being four pairs, the first being the mesothoracic, 2nd 

 1 Bull. Essex Inst. xxii. 1890, p. 24 ; also Amer. Natural, xxx. 1896, p. 591. 



