64 
whose body vertebrae alone may vary as much as one hundred. 
When investigating this character one should record the 
number of body and caudal vertebrze separately and obtain 
their sum. 
VARIATION IN SUM OF GASTROSTEGES AND UROSTEGES 
The number of verterbre in terms of gastrosteges and 
urosteges is subject to a fairly wide range, being from 170 to 
226, a difference of 56. Specimens from Siberia possess the 
highest, those from the Yangtse Valley the lowest, and those 
from Korea and Japan the intermediate counts. 
Examples. Minimum. Maximum. Average. 
“ 70 226 Le 
RARSO: CL VATION ni red-c os sealbe nas ee 152 i 10 
Range in Mainland specimens.........< 109 170 226 193 
emir IVC: sc sts yiins iw ee 6 8 ve 29 195 226 214 
Waetern SToenit. Pipes ss ies one b ea 27 191 202 Loo 
TRON eo eaticis Fo Mined nese males ene ne 24 175 200 187 ] 
GHINMG ntti tert sash) 0s Lae die ee 29 170 185 178 
Range in Island specimens ............ 3 179 200 187 
FIG ROIO: aa ue merice ven) dcr Re PoeY 6 183 195 188 
LONGO iy eae riage veer Cian 23 179 200 1914 
Slengt(n]: qh. aig ae rise orem er eiere cy Gam ar rere a; 2 187 187 187 
linfisebugiai(ay -1anfigat: Meememes rate rare eae mara me Boe 2 185 185 185 
OV EL JES ly acs ped sadn LA 6 aoe 1 eee Wee Kater il 190 190 190 
AVG Gives sr er eur Ohne ean viens i 184 184 184 
TIGEMUULIVIGL © pi. sika bie Vale oa vl ba pre's FRAT 5 182 188 185 
TUSTIN i pao hah awie ee oo ieee © ee 3 182 192 188 
The range of variation in the mainland examples being 
from 170 to 226 and of the Island examples from 179 to 200, 
it is evident that the range of the mainland specimens widely 
overlaps that of the island specimens. 
VARIATION IN GASTROSTEGES. 
Every effort should be made to have the gastrostege 
count an index to the number of the dorsal vertebrae. To 
further this aim it is necessary to ascertain which shield 
corresponds with the first link in the vertebral column. A few 
dissections have shown the most approximate estimate that 
can be made without actually opening the neck is to reckon as 
the first gastrostege the first shield that is of the same width 
as the entire series; it is usually further characterized by 
being colored like the rest of the gastrosteges and not white 
as are the throat shields. 
The shields between the anterior pair of geneials and the , 
first gastrostege are referred to as gulars; they are of two 
types, paired and azygos. Note should be made of their num- 
ber in the record of each specimen, as this will tend to fix the 
first gastrostege, this being the shield from which are started 
many of the counts. 
If the locality of each specimen be plotted on squared 
paper, due regard being taken of the gastrostege and urostege 
