756 
THE HELMINTHOLOGICAL SOCIETY OF WASHINGTON 
THE eleventh regular meeting of the society was 
held at Mr. Crawley’s residence on April 16, 1912, 
Mr. Crawley acting as host and Dr. Graybill as 
chairman. 
In connection with Dr. Ransom’s notes on eysti- 
cerci, Dr. Cobb called attention to a remarkable 
case of hydatid disease in Australia, where a man 
who had had a considerable part of the liver re- 
moved, owing to a hydatid infestation, subse- 
quently returned for operative removal of another 
hydatid. It was found on operation that the 
second parasite was in another part of the liver 
and that there had been a practically complete 
regeneration of the excised portion of the liver. 
The evening was devoted to the exhibition and 
discussion of apparatus, drawings and specimens 
by Dr. Cobb. 
A set of sereens for collecting free-living nema- 
todes was shown, the sereens being oblong instead 
of circular, and therefore easier to pack in a suit- 
case in field work. Two screens using a detach- 
able silk bolting-cloth, instead of an attached 
brass-wire screening, have a new fastening device 
consisting of a string looping around projections 
from the tins. A wooden container for holding 
collecting bottles fits inside of the screens and of 
some collecting trays of the same shape as the 
screens. 
Dr. Cobb remarked that he had secured superior 
results by using sea water in his sublimate fixing 
reagents, nematodes staining very much better 
after such treatment. He suggested that this 
might be due to traces of various chemicals in the 
sea water, rather than to an increased solubility of 
the sublimate used. 
In connection with a number of specimens and 
drawings of nematodes, Dr. Cobb pointed out that 
there is a possibility that some of the free-living 
forms will be found to show traces of internal 
segmentation in the arrangement of the internal 
organs and their relation to the external markings. 
In an undescribed genus he noted the association 
of a strong buccal spear with a weak pharyngeal 
suction bulb, and surmised that the retrorse an- 
nulation in this form served to hold it in a tangle 
of vegetation so that the buceal spear could be 
used effectively in the absence of a strong suction 
bulb to fix the mouth in using the spear. In this 
genus the buccal spear is lost by the male in an 
ecdysis. 
Dr. Cobb expressed the opinion that the study 
of nematodes will have to be separated from para- 
SCIENCE 
[N.S. Von. XXXV. No. 906 
sitology or helminthology as covering a field of size 
and importance equal to that of such subjects as 
entomology. The nematodes make up an isolated 
group with a very wide range of morphological 
structure, life history, habits and geographical 
distribution. The group includes parasites of ver- 
tebrates and invertebrates, parasites of plants on 
land and in water, free-living forms that eat vege- 
table matter, some that feed exclusively on diatoms, 
some that feed on bacteria and some that eat other 
nematodes. Broadly speaking, the mouth parts 
show the same general lines of variation that 
insects show, some being adapted to biting, others 
to sucking or stinging, and it is possible that the 
buceal stylet of Mononchus serves as a poison fang 
to benumb the nematodes on which this genus 
feeds. The life histories and methods of reproduc- 
tion are very variable and include parthenogenesis. 
Nematodes occur in the soil and in the ocean in 
immense numbers and have been found in the polar 
regions. There are probably as many species as 
there are of insects, and some of the well-marked 
genera will probably be found to have as many as 
500 species. 
Some of the nematodes, such as Streptogaster, 
have an anterior dilatation of the intestine which 
appears to be morphologically and physiologically 
a stomach. 
Dr. Cobb gave an interesting demonstration of 
the method of obtaining the decimal nematode 
formula, showing that it could be obtained with 
no great effort in about six minutes. 
MAuRIcE C. HALL, 
Secretary 
AMERICAN PHILOSOPHICAL SOCIETY 
On April 12th, Dr. Willis F. Manges, Rontgen- 
ologist to the Jefferson Medical College Hospital 
of Philadelphia, read a paper before the American 
Philosophical Society on the X-rays. He reviewed 
briefly the history of the discovery and especially 
noted the great progress in safety and efficiency 
of the apparatus and methods of to-day as con- 
trasted with the earlier results. By means of the 
modern methods of protection, X-ray injury is now 
almost entirely eliminated. He discussed the value 
of the X-rays in medicine and surgery both in 
diagnosis and treatment. He pointed out also that 
interpretation of the Rontgenographs required 
special skill, which could only be gained by a wide 
experience or careful training and that there was 
danger in their indiscriminate use in medico-legal 
cases because of the difficulties of such inter- 
pretation. 
