PROC. ENT. SOC. WASH., VOL. 23, NO. 9, DEC., 1921 209 



face-beard long, mainly composed of" black hair?, but lower parr with slender 

 white hairs; lower part of cheeks, behind eyes, with long pure white hair; 

 occiput with erect black hair; proboscis shining black, about as long as the 

 antennae; antennae black, the style not much shorter than the third joint; 

 thorax dorsally with a faint median stripe, obsolete posteriorly, sublaterally with 

 narrow shining ochreous bands, broadest in front; sides of thorax yellowish gray, 

 with black spots, the mesopleura with two small round spots in front, and a 

 broad bar behind, the whole like a grotesque face; thoracic bristles (posterior to 

 the suture) long and black; wings pale grey, distinctly more dusky apically; 

 legs with coarse black bristles, hind tibiae and basitarsi with fine ochreous hair 

 on inner side; halters purplish at base, with a white stem and orange knob; 

 abdomen compressed, the segments viewed laterally showing white apical bands 

 rapidly broadening ventrad, so as to make elongate triangles, becoming con- 

 tinuous with the greyish-white venter; end of abdomen more produced, with 

 terminal lamallae, than in M. rusticus Meigen. 



Compared with a female M. madeirensis, this is readily distinguished by the 

 anterior part of thoracic dorsum, which has only extremely short inconspicuous 

 pubescences, and no dorsal bristles anterior to the insertion of the wings, though 

 there are three notopleural bristles, the anterior one short. The front is dis- 

 tinctly narrower, and the face-beard seems less extensive. The long bristle on 

 under side of hind femora is creamy-white; in madeirensis it is black. In 

 madeirensis the apex of the discal cell, if produced upward, would reach the 

 extreme base of the second submarginal; in portosanctanus it would reach a point 

 well beyond the base. In other respects the two species are essentially alike, 

 and arc- evidently very closelv related. 



Male. Length about 13 mm.; similar to the female except for the sexual 

 characters. The eyes are redder; the hind tibiae are dusky red except the 

 middle third posteriorly, but the color is obscure; the hind tarsi are reddish. 

 The genital armature is similar to that of M. atricapillus Fallen, but the forceps 

 seem to be more slender, and more distinctly truncate in lateral view. 



Type and Allotype. Cat. No. 25049 U. S. National Museum. 

 The paratype sent to the British Museum. 



The genus Machimus has 34 Palearctic species, including five 

 from Spain and one (M. micropygus Becker) from Morocco. 

 Eastward, it extends as far as Persia (M. armipes Becker, M. 

 thoracicus Lw., M. cinguli/er Becker), and Speiser has described 

 two species from the Kilimandjaro region in Africa. Great 

 Britain has two species. Aldrich's Catalogue cites one species 

 (M. avidus U. d. Wulp) from Wisconsin. 



A mosquito and Tipulid I collected at Villa Baleira, Porto 

 Santo, were found by Mr. F. W. Edwards to be "tramp" 

 species, Culex pipiens L. and Trimiera pilipes Fab. 



