A New Order Of The Teleostomi 



Since the publication of the first volume of this journal I have from 

 time to time presented papers on the anatomy, class if ication, and distri- 

 bution of the cybiids, tunas, and bonitos » I am still continuing my 

 researches on these fishes, but as a result of the studies made up to this 

 time I have come to the conclusion that it Is necessary to change the 

 present classification to a degree even greater than that which I have 

 suggested previously o Accordingly I wish to record my conclusions in 

 outline as follows - 



There is a great difference between the fishes which have the dark 

 red muscle tissue ( chiai ) close to the central axis of the body and those 

 fishes which do not, and this difference i3 truly a clearly marked one D 

 For this reason I wish to separate the former from the Teleostei and 

 establish them as a new Order of the Teleostomi, to which I give the name 

 of Plecosteio The fish»e of this Order I wish further to divide into the 

 families Thunnidae and Ka-tsuwonidae D The classification of these s fishes 

 given in Number 1 of Volume 1 of this journal is to be changed so that 

 the family Thunnidae as defined therein becomes the new Order, the genus 

 Thunnus is raised to the rank of a Family, the Thunnidae, and the genera 

 Katsuwonus, Euthynnus, and Auxis are combined into the family Katsuwonidae» 



The new order Plecostei is closely related to the families Scombridae, 

 Istiophoridae, and Cybiidae among the Acanthopterygii of the Teleostei, 

 being closest to the Scombridae in particular o The members of this Order 

 are the most advanced of all the fishes „ For these reasons I believe that 

 th6 Teleostomi should be classified as follows s 



Crossopterygii 

 Chondrostei 

 Teleostomi Holostei 



Teleostei 

 Plecostei 



PLECOSTEI 



These fishes can be easily and clearly distinguished from the other 

 Orders of the Teleostomi by the presence of well developed cutaneous blood 

 vessels o "ith the development of this vascular system there is an increased 

 supply of capillaries to the tissues on each side of the spinal column, 

 forming the dark red part called the chiai . There is a large blood supply 

 and consequently the heart is large o The bones of the vertebral column are 

 very closely articulated, and their zygapophyses are developed dorsoventrally 

 and anteroposteriorly The inferior foramina which appear in the bases of 

 the haemal arches are large and the passage for the blood vessels is broad 

 with a sort of latticework formed ventral to the spinal columno This is 

 especially pronounced in the skipjack » 



