234 NORTH AMERICAN EUMASTACINAE (oRTHOPTERa) 



bushes, with the caudal hmbs strongly diverging and the short 

 antennae erect. Their saltatorial powers are highly developed 

 and they are not at all easy to capture. Constantly on the alert 

 as they are, a swift sweep of the net is the most successful method 

 of securing them. 



The earliest date in the year on which, to our knowledge, 

 adults have been taken is August 8 (Mount Lowe and Echo 

 Mountain), and we have seen no specimens taken later than 

 September 27 (Parker Mountain), but the latter date is probably 

 by no means the end of the season of occurrence, as the insect 

 doubtless occurs much later in the year. Immature material 

 taken June 5 (San Gabriel Mountains) is quite small, while that 

 secured August 8 (Mount Lowe) is as far advanced as the second 

 instar preceding maturity. The latest date we have indicated 

 by immature specimens is September 9 to 10 (Del Monte), 

 where we find the two instars preceding maturity represented. 



Morphological Notes. — The fastigium, when seen from the 

 dorsum, exhibits some variation in its form, width and also in the 

 degree of production, even in individuals of the same sex from the 

 same locality. In some specimens it is more truncate than in the 

 average, and in others it is broader. Features of limb size varia- 

 tion are mentioned under Remarks. The Del Monte series 

 shows a very appreciable amount of variation in the acuteness 

 of the fastigial angle, when seen from the side, but this is due, 

 according to our interpretation, to intergradation through that 

 series with M. c. tamalpaisensis. The exact outline of the eye 

 exhibits some variation in the entire series. 



Remarks. — Typical Morsea californica californica is connected 

 with M. c. tamalpaisensis by means of the Del Monte series, which 

 averages intermediate in most of its features, although certain 

 specimens are nearly typical tamalpaisensis. The form of the 

 male cerci in the Del Monte series is nearly or quite that of 

 taynalpaisensis, but the fastigial and antennal forms are, as a 

 whole, intermediate. An examination of the series before us 

 shows a very decided amount of variation in the proportionate 

 length of the limbs, this being particularly evident in the case of 

 the cephalic and median paire. This tendency is also more de- 

 cided in the male than in the female sex. In the Del Monte series 

 the extremes are quite evident, while in the southern Californian 



