264 
Lieut.-Col. H. Irby on an apparently 
mage, it is as impossible to state to what species it belongs, 
with any certainty, as to accept it as representing some here¬ 
tofore unknown or undescribed form. The specimen was pro¬ 
cured also by Natterer, at Matagrosso. 
I desire to take this opportunity of thanking Herr von 
Pelzeln for his kindness in loaning me these types, and en¬ 
abling me to make comparisons, and thus to obtain more cor¬ 
rect ideas of these specimens than is possible from any de¬ 
scription. 
Thalurania lerchi. 
Besides the types above described, I have lately succeeded 
in adding to my collection the unique type of Thalurania 
lerchi, Muls. & Verr. Ann. Linn. Soc. Lyons (1868). This 
was also placed, in the review of this genus (Ibis, 1873, p. 360), 
among the undetermined species; and I now find that it is 
in no way allied to Thalurania, but constitutes a very distinct 
species of the genus Eucephala, differing from all others in 
having the upper part of the head a beautiful blue, and must 
be hereafter known as Eucephala lerchi. It is stated to have 
been obtained in Columbia. 
XXX .—Notice of an apparently undescribed Species of Corvus 
from Tangier. By Lieut.-Col. Howard Irby. 
Corvus tingitanus, n. sp. 
C. C. affini, Biipp., similis, sed rostro crassiore et setis ric- 
talibus antrorsum directis nec postice recurvatis, necnon 
colore alarum extus plus minusve ferrugineo distin- 
guendus: long, tota 18’5, alee 14‘5, caudse 8, tarsi 2‘5, 
rostri a rictu 2*5. 
Hah. prope urbem Tingem in imperio Mauritanico. 
During a recent visit to Tangier, it appeared to me that 
the small Haven there, hitherto considered to be the European 
species, Corvus corax, was quite distinct from that bird, the 
note or, rather, croak being quite different. This difference, 
difficult to describe, is easily noticed when heard, the note 
not being so hoarse; further, its gregarious habits, as many 
