INTRODUCTION. 
Prot. 8 
INTRODUCTION. 
The number of Titles in the Protozoa Record for 1904 shows some falling 
off compared with that for the previous year, being 371 instead of 433. 
The Recorder attributes this diminution partly to the fact that the 
references were collected (by the Searcher) much earlier in the year than 
has hitherto been the case. It is notorious that many periodicals are not 
received by our Libraries until several months after publication ; hence it 
is quite likely that there will be a certain influx into next year's Record 
of 1904 papers received too late for insertion in the present one. Never- 
theless, allowance being made for the above circumstance, there seems 
little doubt that fewer, rather than more, Protozoan memoirs appeared in 
1904. From many journals in which there were several papers in 1903 
few or none have to be recorded this year. To give one example only: 
instead of over a dozen from the Forschber. Plon, two or three at most 
have been culled. 
If, however, the present Record exhibits some loss in respect of the 
quantity of material, this is certainly not true of the quality. As regards 
the Flagellates, at any rate, the year 1904 must undoubtedly rank as one 
of the most important in the history of the group up till now. And 
not of this class alone has one's entire conception to be fundamentally 
modified as the result of last year's research ! Rarely, if ever, the 
Recorder imagines, has the Protozoa division of the Zoological Record 
contained a memoir of such far-reaching — indeed, almost inestimable — 
significance as is herein included. By general consensus of opinion the 
stupendous revelation of Schaudinn (301) "inaugurates a new era in the 
history of the Sporozoa and Flagellates." 
For the benefit of any who are not already cognizant of this epoch- 
marking investigation, the main facts elucidated may be here stated. The 
author describes the complete life-cycle of two distinct organisms, one a 
Trypanosome, the other possessing the typical characters of a Spirochceta^ 
both parasitic in the blood of the Little Owl, The latter parasite, far 
from being a Bacterium, is, in all essentials, a Trypanosome, and Schau- 
dinn finds that the same is true for other so-called Spii^ochcetce. Both 
these Flagellates have an alternation of hosts and of generations, the 
"carrier," a gnat, being a true definitive host in which — and only in 
which — sexual conjugation takes place. Moreover, for part of the time 
spent in the blood of the bird, the Flagellate is intracellular, acquires a 
gregariniform condition, and becomes, in the case of the Trypanosome, 
what has hitherto been known as a species of H alter idiu7n, and, in the case 
of the " Spirochceta^^^ what has previously been described as a Hcemamoeba " 
or "Leucocytozoon." In other words, two characteristic Hsemosporidian 
parasites are, respectively, only a transient phase in the life-history of a 
particular Hsemotiagellate ! 
So revolutionizing are these discoveries that, in view of the difficulty of 
the subject and the impossibility of following one and the same individual 
through its various phases, one might almost feel inclined to doubt the 
correctness of Schaudinn's interpretation of his observations ; were it not 
for the fact that this author has already contributed such valuable 
additions to our knowledge of the complicated life-history of parasitic 
Protozoa. It is, therefore, casting no reflection on one who may be fittingly 
termed a " prince of protistologists," to say that the corroborative evidence 
— in more than one direction — which is already forthcoming, is highly 
welcome (vide, for instance, Mesnil[234], Billet [20], Leger [184 & 185], 
Brumpt [48], and Rogers [286]). In short, the whole tendency of research 
at present points to a very close connection between the Haemosporidia 
and parasitic Flagellates. 
