370 
The Lung Parasites of Cattle and Sheep, 
obtained by the original find. I was also enabled to compare 
the ingested embryos with certain other small nematoids 
already known to science. It was thus rendered evident that 
our introduced embryos could not be confounded either with 
the so-called Ascaris niinutissima mieroscopica of Goeze, or with 
the Dicelis filaria of Dujardin, or, again, with the remarkably 
worm-like little psorosperm {pionocystis) so fully described by 
Professor Ray Lankester. Altogether, eleven additional earth- 
worms were subjected to experiment. Without further par- 
ticularising the results obtained, I will only [mention that 
at midday on November 1st, when I examined one of the 
newly-infected worms, there were several embryos which 
showed, it is true, no very decided advance of structure as 
compared with what was seen in those which had been several 
days in the soil. Nevertheless, there were slight differences, the 
digestive organs being better defined (Fig. 7, p. 369). At this 
period, however, the weather was excessively cold — a fact which 
may have operated to retard development. The embryos, 
indeed, showed no active signs of life until the application 
of warmth revived them. In great contrast to this inactivity, 
it may be mentioned that one of the earth-worms harboured 
large quantities of ciliated infusoria {Bursarid), which rushed 
about freely over the field of the microscope. 
Embryo passing into the Stage of Larva. — One of the most 
instructive finds resulted from the re-examination of the cut 
ends of the original earth-worm removed from the sifted soil, 
and placed in fresh non-infected earth. This occurred on the 
27th of October. Both halves of the worm had retained their 
vitality, the tail portion being the more active moiety. Unfor- 
tunately, before I had time to examine its contents a pro- 
fessional interruption caused its escape. However, after again 
freely washing the upper half of the worm, I transferred 
its intestinal debris to a glass slide, and at once detected 
a number of larger and more advanced embryos under the 
microscope. They were in a state of marked activity, the 
largest specimens varying in size from to ^ of an inch 
in length. There could, I reckoned, be no doubt as to their 
source, because individually they displayed different degrees of 
organisation, all of them answering to one and the same type. 
A distinct oesophagus was now plainly noticeable in the largest 
specimens, the rest of the intestinal tract being much more 
conspicuous than heretofore (Fig. 8). Not only were the 
characters of the fore-gut, mid-gut, and post-gut well marked, 
but in one specimen there was a complete series of chyle cells,, 
arranged in pairs, most of the cells being furnished with large 
and strongly refracting nuclei. 
