Vol. 8, 1922 
ZOOLOGY: L. 0. HOWARD 
133 
causing a marked proximal migration of the granules. These findings are 
thus in accord with those of Fujita and Bigney in their work upon the frog, 
and opposed to those of Klett, also upon the frog. 
Arey, L. B., 1916. "The Movements in the Visual Cells and Retinal Pigment of the 
Lower Vertebrates." /. Comp. Neur., 26 (121-190). 
Bigney, A. J., 1919. "The Effect of Adrenin on the Pigment Migration in the Melano- 
phores of the Skin and in the Pigment Cells of the Retina of the Frog." /. Exp. Zodl., 27 
(391-396). 
Fujita, H., 1911. "Pigmentbewegung und Zapfenkontraktion im Dunkelauge des 
Frosches bei Einwirkung verschiedener Reize." Arch, vergl. Ophthalm., Jahrg. 2 (164- 
179). 
Klett, 1908. "Zur Beeinflussung der phototropen Epithelreaktion in der Froschretina 
durch Adrenalin." Arch. Anat. Physiol., Jahrg., 1908, Physiol. AM., Suppl. Bd. 
(213-218). 
1 Arey ('16) used the terms distal and proximal to designate the migration of the 
pigment granules away from the center of the melanophore cell and toward that center 
respectively. Hence a proximal migration would bring about what is ordinarily called 
the contracted condition of the melanophore and a distal migration the expanded con- 
dition. 
A SIDE LINE IN THE IMPORT A TION OF INSECT PARASITES OF 
INJURIOUS INSECTS FROM ONE COUNTRY TO ANOTHER 
By L. O. Howard 
Bureau of Entomology, U. S. Department of Agriculture 
Read before the Academy, April 24, 1922 
Since the extraordinary initial success of the Department of Agricul- 
ture in importing the Australian ladybird beetle {Novius cardinalis) into 
California to destroy the fluted scale in the eighties, a great deal of success- 
ful work of the same sort has been done in different parts of the world. 
Most of these attempts have been made in a haphazard sort of way and a 
number of them have succeeded to a notable degree in spite of the rather 
unscientific way in which the importations were made and the lack of com- 
petent scientific study before the importations were attempted. The one 
thing which seems to have been rather carefully guarded from the start is the 
possibility of importing secondary parasites which might destroy the desir- 
able assisted immigrants . Until recently there have seemed to be no time and 
no especial necessity for a careful biological study of the imported parasites 
before the importation has been attempted. Now in many cases such pre- 
liminary studies seem to be very necessary and they are being made. 
One point which has undoubtedly resulted in the non-establishment of 
imported species has been the fact that in their native homes they had 
alternate hosts, feeding during one generation upon one species and during 
another generation upon another. Frequently the alternate host or a vi- 
carious species has not existed in the country into which the parasites have 
been introduced. 
