7068 Insects. 



added an enlarged view of the labium and adjacent parts. This dis- 

 section was obtained from P. denticollis, but the labium is similar in 

 the other species. 



1. Under side of the head of Ptinella aptera. 



2. Labium, with the adjacent parts. 



3. Maxillary palpus. 



A. Matthews. 



Guinley, Market Harborough. 

 May 1, 1860. 



Errata. — I must also call your attention to some errata in my last paper on the 

 TricbopterygidsB, since, in more than one instance, these mistakes change the meaning 

 of a whole sentence. P. 6106, line 4 from top, for " acuminata " read " acuminato." 

 P. 6106, line 18 from top, for " exigua " read " exiguo." P. 6107, line 13 from top, 

 for " determisset '' read " deterruissel." P. 6108, line 6 from top, insert a comma after 

 " differt.'' P. 6108, line IS from top, insert a comma after " calcaralis."— ^. M. 



Note on Brachycentrus subnubilis of Curtis. — This insect has been very abundant 

 here this spring, indeed swarming along both the banks of the river and the still 

 waters of the canal. There appears to be some discrepancy between Stephens' diag- 

 nosis of this genus and that of Dr. Hagen ; thus, Stephens gives " Tibias with a pair 

 of short spurs at the apex ; the intermediate and hinder pair with a second pair below 

 the middle." Dr. Hagen gives 2, 3, 3 ; this is correct ; but the Doctor has inserted 

 a note (?) as to the number of joints in the maxillary palpi ; he thinks two. The 

 note of interrogation may be removed, as two is the number in the males, and three in 

 the females. Now both the authors above quoted give June as the time of appearance 

 for this species. I took them first about the middle of April, and they are now fast 

 disappearing, so that by June I do not think there will be one to be seen. This locality 

 it is true may make some difference as to the time, for more to the north, if possible, 

 they are later in their appearance. The local names of this species I have ascertained 

 tained from a fly fisherman. The male is called the " hare's flex ; '' this, I am told is 

 from the fly-makers using the flex or felt from a hare to imitate this fly. The female 

 is called the " granura," pronounced gran-um ; this I hold to be a corruption of the 

 word greenum, as it is given in consequence of the female having a large green e^^ 

 attached to the apex of the abdomen, which remains attached until carefully deposited 

 in the water, when it rapidly sinks to the bottom, 1 am somewhat inclined to think 

 that Stephens had a different insect in view when he constructed his diagnosis, or I 

 think he would not have made such a mistake in the number of spurs on the inter- 

 mediate and posterior tibiae ; and in this I am somewhat borne out by capturing an 

 insect similar to this, and agreeing with its generic characters, although I did not 

 detect it until I had decapitated it and otherwise mutilated it in dissecting for the 

 generic characters of the genus Brachycentrus. I then found the maxillary palpi 



