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whole dorsal surface of each maxillula is covered with parallel 

 rows of minute spines, and on its inner edge are found a dozen 

 or more elongate, curved teeth. 



These structures had previously been seen and figured — 

 in Helodes excellently by Rolph (1874) and in Dascillus some- 

 what roughly by Rivers (1891). These authors, however, had 

 no conception of the appendicular nature of the organs which 

 they described. Schiödte, in his drawings of the larva of 

 Ateuchus (1874, PI. XIV, fig. 8) shows the hypopharynx with 

 a pair of spinous " paraglossae," which are evidently reduced 

 maxillulas. Ateuchus belongs to the Scarabseida?, the family 

 which includes Geotrupes and Phyllopertha, whose larvae we 

 also examined. In the Geotrupes grub the maxillulae are 

 apparently present, though fused with the hypopharynx, but 

 in the larva of Phyllopertha we can recognise the maxillula 

 on the left-hand side only. Such asymmetry, unusual in the 

 mouth-appendages of insects generally, is very marked in the 

 labrum of Dascillus and of Phyllopertha. It is noteworthy that 

 in these beetle-larvae which possess toothed maxillulae — and 

 especially in Dascillus — there are rows of spines on the labrum 

 which work against the maxillular spines, while median labral 

 teeth are opposed to median teeth on the hypopharynx. Thus, 

 in the mouth of these larvae, there appears to be a dorso- ventral 

 biting or seizing action in the work of feeding. 



Since the publication of our paper, further observations 

 have been made on the maxillulae of beetle-larvae. Scott, in 

 his investigations into the insects living in the wet spaces between 

 the leaf-bases of BromeliaceOus plants in the West Indies, found 

 specimens of a Helodine larva, of which he kindly sent me 

 specimens ; a short account of this larva, with a reference to 

 its maxillulae and hypopharynx, may be seen in his recent paper 

 (1912, p. 431). The accompanying figure (fig. 5) of its labium, 

 hypopharynx, and maxillula may be useful for comparison with 

 the corresponding structures in the larva of Helodes. There 

 is a general likeness between the parts in the two insects, as 

 might be expected, with some interesting differences in detail. 



The labium consists of a flat mentum (M) which carries a 

 pair of palps (p). The front edge of the labium (La) is fringed 

 with a series of long, delicate hairs, and, as usual in coleopteran 



