16 BRITISH TYROGLYPHIDJl. 



first paper * was valuable, interesting, and beautifully 

 illustrated. It introduced the creatures forming the 

 present genus Histiostoma, and gave an exhaustive 

 account of the external anatomy and singular habits of 

 this exceptional genus (or sub-family) ; it also was the 

 first paper which indicated (correctly) that Hypopus 

 was a nymphal stage of some of the Tyroglyphidse. 

 It will be found frequently referred to in this work. 



In the same year (1873) and the following year 

 Megnin published the three papers which contain the 

 views he derived from his investigations into the life- 

 history of Hypopus, f which were rewarded with 

 special honours by the French Academy; they were 

 papers of high importance, and greatly added to our 

 knowledge of Hypopus. They were excellently illus- 

 trated, and introduced a new species of Tyroglyphws, 

 which was admirably observed; still they were erro- 

 neous as to their principal contention relative to 

 Hypopus. The whole of this question, with a summary 

 of Megnin' s views, will be found in Chapter VI of this 

 book, and therefore may be omitted here. 



Some years afterward Megnin returned to a some- 

 what kindred subject with regard to the genus Crlycy- 

 phagus, although the relation between the result of his 

 investigations and Hypopus does not appear to have 

 struck him at the time. He published a short pre- 

 liminary note in 1886, J and a rather fuller illustrated 

 paper in 1888. These investigations overlapped my 

 own simultaneous researches into the rudimentary 



* "Memoire anatomique et zoologique sur un nouvel Acarien de la 

 famille des Sarcoptides, le Tyrocjlyphus rostro-serratus et sur son 

 Hypopus," in ' Journ. Anat. Physiol.,' t. ix (1873), pp. 369378, 

 pis. x xii. 



f " Sur la position zoologique et la role des Acariens parasites 

 connus sous les noms d' 'Hypopus, Homopus, et Trichodactylus" ' C. R. 

 Ac. Sci.,' Paris, 1873, t. Ixxvii, pp. 129132, 2me note, ibid., pp. 492, 

 493; "Memoire sur les Hypopes, Duges," 'Journ. Anat. Physiol.,' 

 1874, t. x, pp. 225244, pis. vii x. 



J " Nouvelle etude anatomique et physiologique sur les Glyci- 

 phages," in C. R. Ac. Sci.,' t. ciii (1886), pp. 1276-8. 



" Observations anatomiques et physiologiques sur les Glyciphagus 

 cursor et spinipes" in ' Journ. Anat. Physiol.,' 1888, pp. 106 110. 



