54 FISHES OF MASSACHUSETTS. 



* 

 The common sizepf this fish is from l?-to 15 feet in length, 



and weighing from 300 to 400 pounds, although it sometimes 

 is taken considerably larger. 



Although a species of " Xiphias" has been known for many 

 years to frequent our coast, I am not aware that it has been 

 examined by any of our scientific men, save by my friend 

 John B. S. Jackson, M. D. of this city, who kindly loaned me 

 his rough notes of a specimen exhibited here in 1833. From 

 these notes it appears, that the " specimen was taken by cod- 

 fishers, from a small dory, about twenty miles from Boston, not 

 far from Marshfield, and near the Western Banks. It was 

 drawn up with much difficulty with cod hook and line, and 

 then speared. Whole length, 11 feet 4 inches. Length of 

 sword, 4 feet. Weight, 650 pounds." 



In looking over the plates of this fish, one is surprised at the 

 great dissimilarities between them j and could he think that 

 each plate had been drawn from a recent specimen, he would 

 be compelled to conclude there must be more than one species. 

 But, as in many other instances, they are probably poor copies 

 of each other ; those points only being particularly attended to, 

 which seem to the copier most important. In Pennant's 

 " British Zoology," the whole interval between the commence- 

 ment and extremity of the dorsal fin is occupied by an im- 

 mense number of minute rudiments distinct from each other. 

 While the figure of S track exhibits but seventeen prominent 

 rays between the extremities, connected by a membrane. The 

 anal also, differs much in the two figures. In the specimen I 

 have just described, it will be remembered that not the slight- 

 est rudiment of a ray was distinguishable upon the dorsal ridge 

 back of the eighteenth ray, until within six inches of the base 

 of the tail. Yarrell figures a young specimen, showing that 

 there is but one dorsal fin, which occupies the whole length of 

 the back, from the gill-covers to within a short distance of the 

 tail. If the reason offered by Cuvier for the disappearance of 

 the greater portion of the dorsal fin be true, viz., " the middle 

 of it being worn with age, gives it the appearance of being 

 double," and of Yarrell, "but the portion of the fin intenne- 



