26 " ''-' i [February, 



In the adjoining county of Devon, half-way between Exeter and 

 Sidmouth, is a district of gravelly heaths, part of which is called 

 Aylesbeare Common, Near some of the boggy spots, suitable for 

 Narthecium ossifragum and cotton-grass, or certain species of Juncus, 

 along the verge of the enclosures, watery places in the hedge-ditches, 

 overhung with lady-fern and other ferns, are resorts of Pericoma 

 laheculosa. Farther to the east, at Seaton, on the coast, is the only 

 known locality for P. decipiens. It frequents a boggy piece of ground 

 on Haven Cliff, overgrown with Equisetum telmateja, in June and July, 

 together with P. fusca. At the base of the cliff, P. pulchra occurs 

 by the streamlet that tumbles down the cliff. P. amligua is found at 

 the same season on Axmiuster Heath or Shute Hill, among alder 

 bushes in a Sphagnum swamp ; also amongst Juncus at Aylesbeare 

 Common, and other places. P. fusca abounded in May between 

 Marston and Mudford (a low-lying district) in the left hand ditch 

 of the main road going to Yeovil, where the water was rippling. But 

 it also resorts to the shadiest part of a small, clean, cattle pond, almost 

 completely embowered in a plantation at Westrow, Holwell. Macquart 

 found it in a wood. 



Pericoma Dalii, up to the present time, has been taken only by 

 Mr. C. W. Dale on his estate at Mullet's Copse, Glanvilles Wootton, 

 among Equisetum telmateja, at the end of May. 



The author has in preparation a Synopsis of Algerian Psychodidoe, 

 in which opportunity may be taken to amend weak points in the 

 leading steps of the tabulations in the present Synopsis, which recent 

 observations have revealed. The two Groups of Genera need re- 

 definition ; a clause noting exceptions should be added to step 2a, vol. 

 iv, p. 32, and the tabulation of Species of the 3rd Section of Pericoma, 

 commencing at p. 123, should be slightly modified, so as to bring 

 No. 24, P. advena, into juxtaposition with No. 18, P. notahilis, each 

 typifying a group of species. 



Explanation of Plates I, II, III and IY. 



Figures of details all enlarged, drawn under the microscope with 

 camera lucida from specimens denuded (with scarcely an exception) of 

 hair or scales. Hair-lines indicate the natural lengths of the wings ; 

 and numerals, preceded by the sign of multiplication, wx'itten small, 

 show the scale of diametrical enlargement of other details. Larger 

 letters (U., P., and Ps.) serve to distinguish the genera Ulomyiai, 



