*4 
Fridtjof Nansen. 
fNo. 
These spermatozoa were motionless, and only a very limited number 
were observed. The description and illustrations (loe. cit. fig. 14) 
which Cunningham gives of these spermatozoa, do not agree with- 
my observations of the real spermatozoa of Myxine, which I have 
;found in the greatest abundance. I am afraid that what he has foundhas 
l)een the abnormal product of an, in this respect, abnormal specimen; 
rat all events, I cannot understand the matter in any other way. 
During a short visit to Edinburgh, in November 1886, 1 was by the ex- 
treme kindness of Mr. Cunningham allowed to see his preparations. 
I thought, then, that what he showed me resembled spermatozoa, 
though there were only a few corpuscles which had this aspect. 
iSince then, I have myself found spermatozoa in the greatest 
abundance in Myxine, and do not know what to say about those 
found by CUNNINGHAM. He gives the following description of 
them: »The spermatozoa possess a pear-shaped head, which is very 
Hhighly refringent, and has a distinct outline; round the posterior 
thicker end of the head is a translucent protoplasmic body, which 
is produced into a long tail«. »In some cases two spermatozoa 
were connected by their tails, and on the connecting thread thus 
produced were slight dilatations composed of clear protoplasm. In 
other cases a celi somewhat spherical in shape gave off two pro- 
cesses, one of which was the tail of a spermatozoon, while the 
other terminated in a point, the head of the spermatazoon belonging 
to the process having probably become detached in the operation 
of teasing. There were also seen ceils in which were present one 
or more structures resembling the heads of the spermatozoa; these 
"heads had however no tails «. As to the process of the sperma- 
togenesis. Cunningham says: »It is evident that the cells and 
spermatozoa described were derived from the spherical cells of the 
rtesticular capsules. These cells apparently develope the heads of 
the spermatozoa which then grow out from the ceils, trailing a 
thread of protoplasm which forms the tail. The curious thing 
about the spermatogenesis observed in Myxine is that the sperma- 
tozoa are attached to the spermatoblast by the tails, and not by 
their heads, as usually occurs«. Those strange statements are 
completely erroneous as regards the structure of the normal sper- 
matozoa, as also the process of spermatogenesis; my investigations 
have led me to no such surprising conclusion, as will subsequently 
be seen, though the testis and spermatogenesis of Myxine is, in 
. several respects, very remarkable. 
