310- 
ficiently acquainted with the distinguishing characters between the 
young larve of Hypoderma lineata and the other species at the time 
when the doubtful determination was made, and am now inclined to 
believe that the specimen was a partly developed larva (third stage) 
of Hypoderma lineata, as the egg or larva of this species is much more 
likely to have been swallowed in milk than that of H. diana, which 
infests deer.* 
An interesting letter called forth from the above experience has al- 
ready been published on p. 275 of this volume of Insect Life from 
Prof. W. M. Schoyen, Government Entomologist, Christiania, Norway, 
referring to a communication of his own on the occurrence of Dipterous 
bots under the skin of man, from which I reproduce the following: 
As pointed out in this article, we know of cases of traveling grubs under the human 
skin in some districts of our country from over one hundred years ago up to the present 
time. Many of these grubs I have myself seen and examined, and they were all of 
the Hypoderma larve (sine dubio—Hyp. bovis), and, as arule, they have accomplished 
longer ramblings under the skin, alwaysin an upward direction, previously to their 
appearance, through an opening in a tumor on the upper part of the body (head, neck, 
shoulders, etc.). All of them have lived in this manner for months, and came out in 
course of the winter months (February, etc.), but were always still much too young 
to go through their transformations. However, I have no doubt at all that they 
belong to Hypoderma bovis, as it is especially with persons who look after or take care 
of cattle inthe summer months that such grubs are to be found during the winter. 
It is evidently the smell of cattle which attracts the bot-fly to them. Hypoderma 
diana does not occur in our country. ; 
The article may be found in the Entomologisk Tidskrift, Stockholm, vol. vii (1886), 
pp. 171-187, and contains also a short historic résumé of all accidents of this kind 
observed up to that time, which have been published here in Norway and elsewhere. 
DIFFERENCES BETWEEN THE LARVZ OF H. BOVIS AND H. LINEATA. 
Dr. Brauer has devised a very convenient and original method of 
showing diagrammatically the spiny armature of the larve of Hypoderma 
by means of which the dorsal and ventral surfaces as well as the three 
rows of lateral protuberances are shown together, so that different spe- 
cies may be readily compared. 
fT reproduce his diagrams (Figs. 45 and 46) of the larve of bovis and 
lineata (bonassi), together with his table for distinguishing the larve of 
the two species. ; 
In the diagrams and table the first two joints are considered as 
cephalic and marked 1, since, as Brauer observes, this is necessary 
for comparison with described larve which as a rule have been consid- 
ered to have but eleven segments. The wide spaces represent the dor- — 
* Reéxamination of the specimens which I have been able to make through the 
kindness of Dr. Freeman, since the above was written, shows that this supposition 
is correct, and that the larva is undoubtedly that of lineata, and is of the second 
subcutaneous or third larval stage—the spiny areas and other characteristics agree- 
ing exactly with this stage. 
The known habits of this larva render this determination doubly sure, and indicate 
that the penetration to the surface may, under unfavorable or unnatural conditions, 
be delayed until the second subcutaneous stage is assumed. 
each Par'yve 
iin 
