2 BULLETIX 1080, U. S. DEPARTMENT OF AGRICULTURE. 
apparently hatched well would have shown considerable injury. Such 
points, however, would only have been brought out by an intensive 
study in the woodland, such as was started later. A few records of 
entire clusters failing to hatch were made in 1907. notably in Xorth 
Saugus, Mass., in woodland near the building then used as a labora- 
tory for the parasite investigations. 
During the winter of 1911-12 plans were perfected for an extensive 
and intensive study of the gipsy moth under natural conditions. 
These plans called for the selection of a considerable number of small 
areas, well proportioned as to type of tree growth and so placed as to 
be representative of the entire infested area. The areas designated 
as '' observation points " were to be followed closely during the entire 
year, with careful notes on hatching of the gipsy-moth eggs, feeding 
of the larvge and the injury done by them, the increase or decrease of 
the infestation from year to year, and many other phases of the sub- 
ject. As the entire problem was built around the degree of infesta- 
tion, it became necessary to have an accurate knowledge of the num- 
ber of egg clusters present in each " point." Therefore, each fall or 
winter a careful count was made, and it was this counting which 
brought forcibly to the attention of those engaged in experimental 
work that some agency was playing a considerable part in the con- 
trol of the moth by killing the eggs. 
The nonhatch problem did not receive extensive experimental at- 
tention until the fall of 1915, when preliminary work was started. 
FIRST INVESTIGATIONS. 
At first considerable time was devoted to the study of the nonhatch 
eggs themselves. Such individual eggs collected a few months after 
the end of the normal hatching season, as well as those 1 or 2 years 
old, were all light gray in color. Careful dissection showed that this 
appearance was due to a complete, closely woven mat of fungus 
mycelium which was pressed closely against the inside of the shell 
and entirely surrounded the dead embryo. The presence of this 
organism in all the nonhatch eggs made it appear that there might 
be some connection between it and the death of the embryo. Cul- 
tural studies were made, and a considerable number of infection experi- 
ments were carried on, which, however, failed to give more than vague 
evidence that the fungus was CA^er more than a saprophyte. It is 
possible that this organism, belonging in the large and rather indefi- 
nite genus Fusarium, is. under conditions particularly favorable to 
itself, a true parasite. However, extensive dissections and cultures 
made of nonhatched eggs as soon as it was shoAvn that they were not 
going to hatch have yielded no positive evidence of its being parasitic. 
The first real study of nonhatch in the field Avas begun in the fall 
of 1916.^ PreA'ious to this a series of egg-cluster collections had been 
made, beginning in August, 1915, and continuing at monthly inter- 
A'als until just before normal hatching time in the spring of 1916. 
Six sets of these collections were made, fiA'e being obtained at chronic 
1 The writer wishes to express his appreciation of the al)I(> assistance ^iven him by 
]Mr. II. I. AVinchester, who helped with the experiments for almost the entire time they 
were conducted. During the time the writer was in the Army, Mr. Winchester conducteri 
all the experiments, and to him belongs the credit for i)launing- and making the summer 
observations on hatching. 
