BIOLOGICAL NOTES ON THE PARASITES. 33 
to the total period passed as larva and pupa. The exact length of 
the pupal period may be defined as between the maximum period 
from observation of the pupa to maturity and the minimum period 
from observation of the larva to maturity. Thus it will appear 
from the following that the total developmental period is over 
twenty-three days, and the pupal stage lasts from six to nine days 
during August and September. 
TaBLeE XX.—Length of developmental periods in Microdontomerus anthonomi. 
In 
Bra- 
Collec- | Pupa : 
tion to Larva to | +o ma-|COnCco Development. 
: maturity maturity. turity coon 
Locality. Date. to ma- 
jturity. 
Maxi- | Mini- | Maxi-| Maxi-| Maxi- Larva + |. 
mum. |mum.|mum.|mum.|mum. | 7°%!- pupa. Fupa. 
1906. Days. | Days.| Days.| Days.| Days.| Days.| Days. | Days. 
Cuero; Tex.255 Js. - August 31...... MANS oes Se esis seine aie Oho saacce| Sees el: See 
Goliad Tex 22-25) -: September 3... Dies ae alice ate es eee iG} nary. 3 3 le eae or el (Gs 
Hallettsville, Tex...) August 30...... 14 9 | 9 | GP ees SS | ah ene eee eV eee 6 
Wiaico, Tex Js. 452)" August 28, 29... 10 | 9 | 9 53 (3) eee Se eee ee lee ah de 
roe Nai foreras | Neate ral oeisiniavne > arnavelels| ne acai sies 23+ 23 6-9 
It was impossible with a lens to find any characters to distinguish 
the larvee of this species from any of the other chalcidoids, as all of 
the chalcidoid larvee concerned in this report are finely, transversely 
lineolate and clad with a few hairs regularly placed in a line around 
the middle of each segment. The pupa is nearest in appearance to 
that of Cerambycobius. The female pupa is robust, brown until 
almost mature, with no darker spots on the dorsal abdominal seg- 
ments, but with three longitudinal white lines and a transverse 
white line on each segment; the ovipositor is appressed to the dorsum 
and proportionately longer than in Cerambycobius. The exuvium 
is easily recognized by the form of the ovipositor and its brown color. 
(See figure of pupa and of chalcidoid larva, Pl. I, figs. 4, 7.) 
A most interesting point in the biology of this parasite is the 
fact that a number of individuals were bred from Bracon cocoons. 
This is one of those phenomena which are here designated as accidental 
secondary parasitism—that is, where a natural primary parasite finds 
its host consumed by another parasite and in order to retain its hold 
on life is compelled to attack that parasite itself. 
10292—Bul. 73—08——3 
