SEASONAL CYCLE IN PERCH SPERMARY 685 
The weight and size of the testis is proportionate to the weight 
and size of the body. For example, at one season of the year the 
weight of the testis of a fish weighing 97 grams was 5.25 grams 
while that of a fish weighing 40 grams was 2.25 grams. In the 
first case the weight of the testis was one-eighteenth, and in the 
second it was one-seventeenth of the gross weight of the body. 
While the actual weight of the testis cannot be taken as a reliable 
criterion, therefore, for the volumetric variation of the testis, the 
proportion between the weights of the body and of the testis 
will be fairly constant for a large number of individuals for any 
given season. Hence, in constructing a curve to show the varia- 
tion in the volume of the testis in different seasons, the propor- 
tion which the weight of the testis forms of the total body weight 
has been taken as the unit by which points may be determined 
for a curve. Figures 5-22 represent a series of camera-lucida 
drawings showing the variation in size and in shape during the 
different seasons. Figure 7A represents the variation graphi- 
cally, and the accompanying table gives the figures upon which 
this curve was based. 
= == a ai AVERAGE RATIO 
Dare werent or | werant or | ,BETWEEN 
musth ANOISNAS BODY WEIGHT 
grams grams per cent 
aI ull yale ews Petet ep eeges 2 He Oey, A Ole Aah 78.4 0.1 0.12 
UDI ace Wayne alba an 9 i oa eNO ae pana ee ot 68.2 0.1 0.14 
TNT OV LAT ISH A Seer amo eas eens eee se ee eee ics (ay Onl 0.14 
AANTDTEATISI SS eee esr eat arse rae vane A Ae en ahh aN chen 72.48 0.177 0.21 
Sepuemiben Wh apres tines geo aun 89.7 0.37 0.47 
Sepvemben lost ja arene Was ame ree: 60.98 0.726 1.19 
Octobertli peters eek ein eee ae 72.00 2.46 3.44 
Octobe sl ony nei verre eines Se ME mesh & 78.2 4.15 DEo2 
INI Oy Sita over eI GS A se ee ae ere UD sh 4.44 5.88 
DE cemib erplieptrc erm erent tes 84.00 4.2 5.00 
ROMMUTANay alae Mert ny Athen oti sacahe oo Aun wesiehs cite & Ges 67.5 3 2al 4.76 
SHG NE Meer tay oulseeante SAC epee Aes gen ach as 72.6 3.16 4.34 
Nair isan, Seba des ante eee oe 91.4 4.15 4.54 
ZsNy oC [RR hg ih, cae i RM APU: Sed gt 75.3 2.78 3.70 
ANVONENIP TIES) Seve ene IR cee Clclgs RABAT A Sis oe 68.8 2.86 4.16 
INTe ihe ares s, Mey pore sete cient Mant fat 1 76.7 1.91 2.50 
IN aiy all SARs cre in emer et adnate (ees 0.84 1.62 
JUTe Re er pas 7, saa Ce Ree ay ee eee a 81.4 0.26 0.338 
Jiu eye ea cori ee Pe eee pty cg eo eee 85.00 0.15 0.17 
