17 
Legs. It is characteristic of Agrotids that the mid and hind tibiae are 
spined to a greater or less degree. Hampson places several genera among 
the Agrotids which show no spining on the mid tibiae and a greatly reduced 
spining on the hind tibiae. The writer has, however, in a previous article 
pointed out that the only North American genus included, viz., Protagrotis 
Hamp., is essentially non-Agrotid and is much better placed near Luperina 
and Sidemia. It is well-known that Sidemia devastator Br. frequently 
shows a single spine on the hind tibia. 
The fore tibiae may be spined or unspined, and this character has been 
largely used by most recent revisers as one of the primary means of separ- 
ation. The writer, too, has found it a very useful character, but on the 
border-line between “spined” and “unspined” it cannot be satisfactorily 
used without separating species obviously allied on genitalic characters. 
For this reason the writer has included in such genera as Anomogyna and 
Anaplectoides, species wnich may be entirely without fore-tibial spines 
along with those in which one or two weak (and generally concealed) 
spines may be discovered by careful examination. 
In the higher, and possibly more recent, genera, such as Euxoa and 
Agrotis, the fore tibiae constantly show complete inner and outer rows of 
strong spines (at times almost claws), this development going hand in 
hand with a shortening of the tibia as compared with the first tarsal joint. 
As we descend the line of genera we note that the spines become weaker, 
next that the outer row is reduced to spining on the apical half with lateral 
hair-tufts replacing the spines on the basal portion; following this there is 
a corresponding reduction of the inner row until we reach forms, as men- 
tioned above, in which only a single weak apical spine on the inner side 
persists, and other allied forms which appear to be entirely unspined. 
Farther down the scale again are genera such as Abagrotis in which the un- 
spined condition of the fore tibia is a normal and constant feature. 
The presence of a fourth outer and sublateral row of spines on the 
tarsi (best seen on the mid tarsi), noted by Forbes, seems to offer at times 
a very satisfactory character for separation. It is quite generally present 
in the higher, strongly spined genera, and for this reason the writer is 
inclined to consider it a recent acquisition, indicating a more advanced 
degree of development. The spines in this row are never so numerous as 
in the three ventral rows and, as usual, species occur in which only traces 
of these spines are present; in such instances, for example prasina Schiff., 
the character must be used with great caution. On the other hand the 
writer has noted that in cases where species, heretofore closely associated 
in our lists, have differed in the presence or absence of this row of spines, 
the genitalia have also shown marked distinctions, and, therefore, the 
writer is inclined to lay considerably more stress on the value of the char- 
acter than did Benjamin in his Lampra revision. 
Male Genitalia. Since Smith's revision in 1890 no further detailed and 
comparative study has been made of the male genitalia of our North 
American species. In this bulletin a single clasper (or as Smith called it, 
liarpe) of numerous species was figured, but Smith’s method is open to 
criticism in that his rather crude figures give no idea of the whole organ 
and the interrelationships of the various parts; the writer believes it was 
his custom to break off one clasper in a dried condition and figure as much 
