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KAMAKICHI KISHTNOUTE: 
macropterns in the first and second years seems to be nearly the same as that 
of the common tunny; but in the young form of Thunnus germo reticulating 
longitudinal bands are found, instead of transverse bands. 
The smallest specimen of Katsuwonus pelamis in my collection is 21 cm. 
in the total length. It has a slenderer body than the adult, three dark 
oblique ma rkings at the back of the caudal portion, and one faint longitudinal 
band under the lateral line. This specimen was caught in August, 1916, at 
Okinawa-ken, and seems to have been a fish hatched during the same year. 
The smallest specimens of Euthynnus yaito in my possession are 13 cm in the 
total length. One of them was sent by Mr. Gobee. It was collected by the 
SS “ Gier ” in November, 1907. The other specimen was collected near 
Keelung, Taiwan, in 1919. They are very slender and have eight or more 
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transverse bands on the side. These bands are nearly vertical and fade toward 
the ventral median line. When they grow to a total length of 19 cm the body 
becomes very broad, the thoracic spots appear, the bands gradually disappear 
from the ventral part, and the dorsal part of the bands becomes oblique. 
Mr. S. Tominaga sent me several immature specimens of Auxis maru, 
which he obtained from the stomach of striped bonitos, caught off Awakunijima, 
Okinawa-ken (Ryukyu). They measure 11-17 cm. in length. The largest 
specimen is nearly the same form as the adult, but the specimens, 11-13 cm 
in length, are remarkably slender. The skin is more or less damaged by 
gastric juice, and the markings are not found in these small specimens, but 
in the largest specimen, there seem to be some transverse bands. They were 
collected on July 10, 1921. 
LOCOMOTION. 
About the locomotion of the fishes of the Scombridae and Cybiidae there 
is nothing new or peculiar. It is quite similar to that of other teleosts. 
Swift and unceasing locomotion is, however, characteristic of the Plecostei. 
It is impossible for fishing boats, running about 10 knots an hour, to 
accompany a school of the striped bonito in progress, so that fishermen 
throw out live baits to attract and thus to retard or stop the progress of the 
school. Plecostean fish scarcely bend their body in locomotion, except the caudal 
peduncle, as will easily be understood from the form and construction of the 
