250 A. C. OUDEMANS, NOTES ON ACARI. 
5. Thecarthra bouveti (Megn. et Trt.) 
This species, hitherto only reported as inhabiting the 
spools of the great quills of Charadrius hiaticula L., was also 
among numerous other mites found by Dr. Trouessart in the 
spools of quills of Totanus totanus (L.). The anal suckers are © 
of moderate size, brown, and well developed, not rudimentary. 
6. Plutarchia chelopus (Trt. et Nn.) 
(With Plates X, fig. 30—35, and XI, fig. 36— 39). 
1894. Syringobia chelopus série anormale parthe- 
nogénétique syringobiale Trouessart in Ann. Soc. 
Entom. France; Bull. Entom.; Seance du 9 Mai et du 23 Mai. 
1898. —— series anomala sive parthenoge- 
netica. Berlese, A. M. S., fasc. 88, n° 2 (non n° 1) (see 
the foregoing species). 
1899. —— série normale Trouessart in Soc. Biol. 
Paris; volume jubilaire, p. 624— 633. 
1904. Sept. 1. Plutarchusia (corr. Plutarchia) chelopus Oude- 
mans in Entomol. Bericht. n° 19. p. 173. 
This species is considered by Trouessart and Neumann as 
an abnormal and parthenogenetical series of Syringobia chelopus. 
I do not say that it is not parthenogenetic, but I doubt of it, 
for 15 among 30 females there were 3 males, a numbre of 
males large enough to fertilize all the females, and 224 Trouessart 
has not been able to detect the copulation aperture on the 
deutonymphal skins; probably it is situated in the posterior 
margin; and on the other hand I have not always seen with 
certainty the copulation-aperture in the deutonymphal skins 
of Syringobia chelopus. 
Larva. (Fig. 30, 31). Length 470 a. Colour pale, 
shields and legs yellowish. Shape very elongate, at least 
three times longer than wide. Texture smooth in the shields 
and legs, finely wrinkled in the unprotected parts. 
