46 College of Forestry. 
fore the nuptial chamber is prepared for his mates. When 
he is engaged in making the entrance burrow, with the fore- 
part of his body in the bark and the rest entirely exposed, he 
is easy prey — although it must be confessed not exactly con- 
spicuous prey — for all sorts of predaceous insects and birds. 
Then, too, many males are doubtless washed from their bur- 
rows and drowned by beating rains and we know it to be true 
that at least a small proportion are overcome by exuding 
pitch. The females, on the other hand, do not leave their 
larval host until several days later than the males and by 
that time the nuptial chambers are completed and as soon 
as they enter they are well protected by the burrow and well 
guarded by the vigilance of the male at the entrance. As 
the beetles fly only on warm bright days, the females would 
not even be exposed to the danger of a rain storm, provided 
they found a burrow to their liking within a reasonable 
length of time. 
Summary oF Lire Hisrory.— The life history of P. hop- 
kinst may be summarized as follows: 
SIEGE D Wee SUATUCH Woe saints e nts “oly %.2) 0%e March 15 
Nuptial chamber completed but only 
Mili @gPRESCMAA + ost < Miege ius ceeded = ch ene - March 21.... 6 days 
Renialegtertulized? 2s ..cic%2. 6 aks March 23.... 8 days 
Several eggs already laid......... March 24.... 9 days 
Male accidentally killed.......... March 25....10 days 
Mirsteges, hatched «....)0..0..5. 5. March 31....16 days 
Female. ceased; laying. ............ April, 2....18 dayg 
Larvae transformed to pupae...... April. 20....36 days 
Pupae transformed to adults....... April 26....42 days 
New generation emerged 1 Ne 6: Da 
eke a) P RAp hes, May 30....76«days 
First brood burrows of new genera- 
plane strode. ices abet - May 20... ..66idaye 
The above data was all derived from a single brood bur- 
row designated as “ Burrow H” in the notes. It was, how- 
ever, carefully checked up with other burrows started at the 
same time and at other times and represents the norm of 
lnhoratory conditions. 
