18 



Fishery Board for Scotland. 



does the second ray grow reguiarly with the increasing length of the fish. The 

 first ray, however, although starting late, grows uniformly but more rapidly in 

 proportion to the increasing length of the fish, so that in the largest specimen 

 examined, the first ray is almost as long as the second. 



The measiirements of the small specimen described by Fulton (1902) may now 

 be compared with those given for the present series in Table I. The following 

 are the comparable measurements : — 



In percentages of 

 Length without caudal. 



If due allowance is made for differences which may arise through the selection 

 of different points from which the measurements were made, it is seen that Fulton's 

 specimen can be placed in its position in the series, and these independent measure- 

 ments give ample justification for the correctness of the deductions regarding the 

 developmental changes. 



Other Small Bottom Forms. 



Two small specimens, 94 mm. and 78 mm. long respectively, from the West 

 Coast of Norway, have already been described by Diiben and Koren (1844) as 

 LopJiius eurypterus. Giinther (1861) compares these two specimens with small 

 forms from the Mediterranean, and although there are many points of difference, 

 he concludes that they do not belong to a separate species, but are LopJiius pis- 

 catorius. Considerable difficulty arises when one tries to compare either Giinther 's 

 specimens or the Norwegian specimens with the present series, especially regarding 

 the relative proportions of the different parts. Giinther does not state definitely 

 the sizes of the Mediterranean specimens, although one may infer from tho^e 

 figured and described that they are younger than the Scottish or Norwegian ones, 

 the post-larval characters being still well marked. The short description given of 

 the Norwegian specimens is also applicable to the Scottish specimens. " The 

 head is broader than long — its length (from the extremity of the snout to the margin 

 of the gill-cover) being one half of that of the remaind.er of the body, the caudal 

 fin not included. The dorsal spines are comparatively short, the length of the first 

 being only one half of that of the second, or one-fifteenth of the total length of the 

 fish ; the first terminates in a transverse cylindrical knob, which is provided with 

 minute cilia ; the two others have alternate fringes on both sides. The spines 

 which form the continuous dorsal are similarly fringed, and the rays of the soft 

 dorsal project very slightly beyond the membrane. The pectoral is exceedingly 

 broad, and extends beyond the margin of the anal. The ventral also is broad and 

 can be expanded like a fan." 



In the Norwegian specimens, as figured, the length of the pectoral fin appears 

 to be in fairly close agreement with the Scottish specimens of similar size. It has 

 already been pointed out, however, that all measurements of the paired fins are 

 open to objection unless the points from which the measurements have been made 

 are given, and that the length of the young form is also taken into consideration. 



The Scottish specimens show that the first ray is late in developing, but that, 

 as the fish grows, the first ray increases at a greater rate than the others. The 



