190 
the t])t=*or}- of infection h\' tlu* skin ‘ now stands on the firnj foundatioL 
of experimental proof.' Ikil the printed abstract (,|oura Trop.iled 
190S. p. 34) tlien goes on to s;iy that * Dr. SaMBON doubtnt, homft. 
whether tlie trachea-ocsopluigii.s part of the journey wjls more tiia; 
conjecture; he thoufjht the larvae isnild cvrtainly reach the inleste 
by n safer and more direct route.' ( lie atitlxfr tla'ii refers to the 
larval stages of certain C'ylicostoincs found encysted in the intestim 
wall, and to the larvae of Sc/eros/omum t ulgarf living in aneurjsn- 
of tlie mesenteric arteries, m horses. I presume that Dr. SAm\ 
means to indicate by this reference that there is a connection, or an 
analogy, between the development of the forms mentioned and tbai 
of the Ankylostomes. If my presumption is correct, I maysayin 
answer that thoughts of this sort are as old as they are unfoundec 
They will be discussed in detail in the second part of my iDOOOgrapli 
on Ankylostoma which I am at j>rcscnt writing. If Dr. SA^!B0^ 
further thinks that the larvae could ’certainly’ reach the intestine 
by a safer and more direct route, ami if lie ‘doubts’ whether flie 
trachea-oesophagus part of the journey is * more than conjecture, 1 
cannot help it. I will only stale the following facts. My actaal 
observations concernbig the wanderings of the larvae were first niado 
known in a paper read before the Sixth International Zoological 
Congress at Berne in 1904. They are printed in the 'Comptes 
rendus’ of this Congress (1905a, p. 225f.), and again described in 
connection with some other questions concerning Ankylostomiasis in 
a ater paper of mine (1905b). In Berne I exhibited a series of 
microscopical sections showing the larvae in the different stages ot 
journey. Tliese preparations afterwards went for some time 
1 A \ ^^"^^^stle-on-Tyne, who, with my authorisation. 
antern slides of some of them made which he used in connection 
Min- of England Institute of 
were Mechanical Engineers (1904). Some of these photographs 
in Sir ^ ''egret to say, without my authorisation) published 
Irf-f r ■ Lectures o„ Tropical Diseases' (.905)^ 
shovvinD-°T showing larvae in a bronchus, and another 
■t rrch'r;" ^ ^ - erroneously hbeaed. 
a detlLI lT“' of preparations, Lmpaniedhy 
data,led descnpt.on, of all the important stages of the journey of the 
