284 GEOLOGICAL SURVEY OF THE TERRITORIES. 
River shales, but the tertiary beds of British Columbia have furnished 
a single species of Ilemerobidae belonging to an extinct genus allied to 
Micromus, and which I have called Bothromicromus. The number of 
species of tertiary Planipennia is nearly doubled by the discoveries 
already made in the American tertiaries, but the families and especially 
the genera are very differently represented on the two continents. Inthe 
European tertiaries, the Raphidiidae have only one species of Inocellia ; 
while on the other hand the Hemerobidae show one or more species each 
of Nymphes, Sisyra, and Hemerobius, besides the species of Osmylus 
mentioned; the Chrysopidae, as stated, are unrepresented, although 
two species are indicated by Hagen from the Jura of Hichstatt; the 
Panorpidae have one species of Panorpa and three of Bittacus; while 
there are also two species of Ascalaphus and one each of Coniopteryx 
and Chauliodes, belonging to families not found at Florissant. To pass 
to other Neuroptera: Embia, too, is represented in Europe by a single 
amber species, and there are no less than thirteen species of four genera 
of Perlidae, a family unrepresented in America, and eight species of five 
genera of Psocidae already described, and a number more shortly to be 
published by Dr. Hagen; of the latter family Florissant has one highly 
interesting species of a new genus, Necropsocus, which seems in some 
measure to unite its two divisions of Atropina and Psocina, and to be 
curiously related to one of the interesting genera from the amber which 
Dr. Hagen will soon make known. Larvae and pupae of three species 
of Epbemeridae and an imago are also found at Florissant; immature 
stages of Ephemeridae have not before been found fossil, and only a 
single winged Ephemera has been indicated from the tertiary rocks of 
Kurope (Oeningen), but the Prussian amber has furnished seven species. 
A very interesting species of Lepisma also occurs at Florissant, the first 
known from any rock formation, but here again the amber discloses no 
less than sixteen species of Lepismatidae, besides ten other Thysanura. 
The Odonata furnish the first opportunity that has been embraced of a 
comparison between the insect faunas of Florissant and the Green River 
shales; the Florissant beds have furnished six species in the perfect 
state besides two larvae; the Green River shales four species in the 
perfect state besides fragments of another, concerning which nothing 
more can be said than thatit probably belongs to the Libellulina; two 
of the Florissant forms belong to Aeschna, besides one of the larvae ; 
all the remainder, four Green River species, and four from Florissant, be- 
sides the other larva, belong to the Agrionina; the Green River shales are 
represented by one species of Podagrion and three species of Dysagrion, 
an extinct genus of the legion Podagrion allied to the genera Podagrion 
and Philogenia; the Florissant bed by two species of Agrion and two 
of Lithagrion, an extinct genus with the same alliances as Dysagrion ; 
the species of Agrion are not sufficiently perfect to decide into what 
subgenus they will fall, but they are certainly closely related to each 
other, and appear to be most nearly allied to Amphiagrion, or else to 
Pyrrhosoma or Erythromma; all the Green River species then belong to 
the legion Podagrion, while the Florissant species are divided between 
the legions Podagrion and Agriou; the resemblance of the fauna of the 
two localities is very apparent, though the species and even the genera 
are wholly distinct; the facies of both faunas is decidedly subtropical. 
The European tertiaries have proved far more productive in Odonata 
than the American, nearly fifty species having been indicated, of which 
about fourteen are larvae or pupae; as in America, the Agrionina are 
the most numerous, having eighteen species and mostly representing 
the true Agrionina (America nine species, wholly Agrionina proper) ; 
