128 MR, B. F. CUMMINGS OX THE 



10. Oil some Points in the Anatomy of the Mouth-parts 

 of the Mallophaga. By Bkuce F. Cummings *. 



[Received October 17, 1912 : Read November 26, 1912.] 

 (Text-figures 24-32.) 



Index. 



Structure or Morjihology : Page 



Palpi of the Ischiiocera 128 



„ ,, Amblycera 128 



Tlie cesophageal sclerite and glands 129 



Varieties of sclerite and glands 130 



Distribution of sclerite and glands 133 



Descriptions of special cases 133 



The maxillarj' forks : 139 



Taxonomy : 



Conclusion 140 



The Mallophaga are for the most part such small parasites 

 that the dissection of the manclibulate mouth is often a matter of 

 considerable difficulty. It seems scarcely sui'prising, therefore, 

 that a good deal of misunderstanding has arisen in regard to 

 the mouth-parts, and in the literature which deals with this 

 subject a variety of opinion will be found on such questions as 

 the palpi, the oesophageal sclerite, and so on. 



The Palpi of the Ischnocera. 



In a paper in the P. Z. S. 1909 (1), appear figures and de- 

 scriptions of the Ischnoceran species Go7iiodes tetraonis Denny, 

 from the Grouse, hi which a pair of very minute one-jointed 

 appendages is shown to exist on the labium below the para- 

 glossse. In G . falcicornis N., I can find no trace of these minute 

 appendages, which perhaps represent the palpi of the second 

 maxillse. In the same place, the second maxillae of G. tetraonis 

 are described as rounded with certain setfe or hairs, whence it 

 appears that in this species they are less degenerate than in the 

 other Ischnocera so far examined, Avhere the second maxillse are 

 usually obsolete, flat lobes without palpi, thinly chitinized (or not 

 chitinized at all), and situated within the mouth-cavity behind 

 the mandibles. From the figures of both G. tetraonis and 

 another Nirmus cameratus N. they are omitted, and instead, the 

 paraglossse of the labium are labelled first maxillae and the 

 minute appendages second maxillae. 



The Palpi of the Amhlycera. 



The other suborder, the Amblycera, is distinguished bj'' the 

 presence of a pair of jointed palpi absent from the Ischnocera. 

 The view of Nitzsch, who first considered them in 1818 (2), may 

 at length be considered as sound, namely, that they belong to the 

 first maxillge and not to the labium. Grosse (1885) (3) assigned 



* Communicated by the Seceetaky and published by permission of the Trustees 

 of the British Museum. 



