Reproductive Cycle in Normal Male Frogs. 
Speci- 
men. 
Time of year. 
Weight in 
yr. 
Condition of thumb. 
1 Condition of testes, j 
g- 1 
April 18tli 
About 22 
Pigmented pad of' 
breeding- season has 
been shed, but 
marked colourless 
papillte are present, 
giving pad a rough 
texture. 
Sperm has been 
shed, testis is 1 
small. Only 
spermatogonia 
present, and 1 
remains of sup- J 
porting cells. 
g- 2 
Ditto 
About 20 
j Pads quite smooth, 
no papillae to be 
observed. 
: h. 1 
May 9th 
About 20 
Practically smooth, 
a trace of papillae 
! which hardly project 
above genera l surface. 
Ditto. 
: h. 2 
Ditto 
About 18 
Papillae well marked, 
nearly as in g. 1. 
j. 1 
June 20th 
27o 
Papillae fairly well 
marked, not so large 
as in g. 1 or h. 2. 
Testis increased > 
in size ; marked j 
formation of 
j. 2 
2 L 
Practically smooth. 
masses of 
j 3 
16 
Slight papillation. 
spermatocysts. 
j. 4 
14 
Smooth. 
j- 5 
10 
„ 
k. 1 
July lltli 
24 
Active multi- 
i k. 2 
9 
22 
plication of 
: k. 3 
k. 4 
14 
7 5 
; 
spermatocysts. 
1. 1 
Aug. 1st 
16*5 
Smooth ; marked 
increase in glands. 
Spermato- 
genesis in full 
1 1. 2 
, 
155 
Very slight papillae. 
process. Sper- 
1. 3 
, 
125 
99 
matids present 
. 1. 4 
8-5 
Smooth. 
in places. Testes 
1. 5 
1} 
4 
very large. 
m. 1 
Aug. 
22nd I 
21 
Very slight papillae. 
Spermatids and ! 
! m - 2 
26 
Papillae marked. 
ripe sperma- 1 
m. 3 
, 
19 
Smooth. 
tozoa in many 
1 m. 4 
[ m. 5 
” 
17 
15 
Very slight papillae. 
tubules. 
1 m. 6 
105 
Smooth. 
n. 1 
Sept. 19 th 
25 
Papillae well marked. 
All tubules full 
n. 2 1 
I 
22-5 
Papillae highly 
marked. 
of fully formed 
spermatozoa. 
n. 3 , 
20 
Papillae marked. 
Absence of any 
n. 4 
16 
Papillae highly 
marked. 
other stages, 
except 
n. 5 
125 
Papillae marked. 
spermatogonia 
| n. 6 
9 
lining tubules. 
Spermato- 
genesis definite- 
ly finished. 
o.-u. 
Oct.-March 
Continued increase of 
papillae up to breed- 
ing period. 
Testes remain 
unaltered, 
until shedding 
of sperm. 
