WALSH DESCRIPTIONS OF X. AM. HYMENOPTERA. IO3 



-except sometimes towards its base, is not ferruginous but black. Joint i 

 is yellow, with a black, or sometimes ferruginous, round spot on each 

 side i of the way to its tip, which two spots are generally more or less 

 •confluent with the base and with each other; and the terminal i of joints 

 2-7 (not merely of 1-4) is jellow, but more obscurely so on the last joint 

 or two. In a single $, there is a large, lateral, roundish, yellow spot 

 just forward of the tip of the black basal i of joint 2. Length (^ .^"j-.^g, 

 $ .49-.57 inch. Front wing j- .40, $ •42--45 inch. 



Two c?, four $ ; all taken in August on Golden-rod and other 

 ■flowers. Perhaps as this species was described by Cresson from 

 alcoholic specimens, taken in Colorado, its true coloration was 

 partly misstated. To some colors alcohol is absolutely ruinous. 



CeratOSOma fasciata, Cress.— (5* ?•— Differs in no respect from the d* 

 $ apicalis described above, except, ist, in the large spot on the occiput 

 being generally in i' (but not in $) rather black than ferruginous, and in 

 its being occasionally more or less confluent with the black spot above the 

 antennae ; 2d, in the quadrate yellow spot on the disk of the mesonotum 

 being smaller, and generally but not always isolated; 3d, in the yellow 

 lateral spot on the anterior \ of the metathorax being usually smaller, 

 occasionally obsolete, and never confluent with the yellow terminal i of 

 the metathorax; but especially, 4th, in the apex of the front wing being, 

 not hyaline, but pale brown like the rest of the wing. In not a single 

 specimen (?$ is the face or clypeus partly ferruginous, as aficalis $ is 

 described by Cressou ; and all the variations noted above under apicalis 

 occur here also, with the single exception of the last one enumerated. 

 Length <S .33-.48, $ •45--47 inch. Front wing rf .32-.40, $ .37-.40 inch. 



Twenty-four d", four $, all taken in August in company with 

 ■ apicalis on the flowers of the Golden-rod. It appears from the 

 above that there is not a single perfectly constant character to 

 separate these two species, except the hyaline tip of the wing of 

 apicalis^ which is absolutely invariable, and towards which no 

 -approximation whatever is made in the 28 specimens oi fasciata. 

 And yet these two very closely allied but perfectly distinct species, 

 each represented by numerous specimens, occurred promiscu- 

 ously in the same w^eek in the same very limited locality. To any 

 ■one who disbelieved in the present existence of species, this would 

 be a suggestive fact. To those who believe that species have been 

 distinct for all time, the Unity of Coloration that we see in these 

 two highly ornamented species offers an insoluble enigma. 



GE3srus TRYPHON, Gravenhorst. 



We have but to refer to the descriptions of this genus given by 

 authors to see that, like many others in Ichneumonidce ^ it is a 



