122 REPORTS ON THE STATE OF SCIENCE. 



extent on the weather. A long spell of fine calm weather appears to 

 send the whales farther out, whereas dull, cloudy, and rainy weather 

 brings them in. This is especially the case with the Mystacocetes, and 

 is probably almost entirely due to the movements of the plankton on 

 which these whales chiefly subsist. Of course in very rough weather 

 the whalers find it impossible to handle the whales even though they 

 may be seen. 



I. Measurements. 



A definite and, wherever possible, complete set of measurements was 

 taken of every whale examined. It was found impracticable to obtain 

 the distance between the tips of the tail-flukes as intended, as most 

 of the flukes are cut off directly the whale is captured to reduce the 

 resistance when towing into the station. 



It is intended to examine these measurements more closely later on, 

 but a few general conclusions may be noted. 



Balcenoptera musculus. — Average length of whole catch = 61 feet 

 9 inches. Number of males = 12. Number of females = 12. 

 Average length of males = 61 feet 1 inch. Average length of females 

 = 62 feet. 6 inches. From these results it seems, as is generally 

 supposed, that about equal numbers of each sex are captured, and that 

 the females are slightly larger than the males. As far as can be ascer- 

 tained without going into the figures closely, the general proportions of 

 these Rorquals agree with those already published by other observers. 



B. sibbaldii. — The average length of the three Blue whales examined 

 was 76 feet 2 inches, but of these one was much smaller than the other 

 two. All these were females. 



All of the above measurements only refer to the whales captured 

 after my arrival. The total lengths of those caught before this have 

 been obtained, however, so that the averages will be more trustworthy 

 when these are taken into account as well. Unfortunately the sex of 

 the individuals is not noted at the station. Corresponding measure- 

 ments were taken as nearly as possible in exactly the same way, but 

 the weight of the animal distorts the shape of the body when on the 

 flensing slip, so that exact correspondence cannot always be obtained in 

 some measurements. 



II. External Form. 



The general form of all the specimens seen agreed with previous 

 descriptions of the species. In two cases in particular among the 

 Balcenoptera musculus the pectoral fins on either side did not corre- 

 spond exactly in size. In each case that on the left side was distinctly 

 the larger. 



In both B. musculus and B. sibbaldii the pectorals ended in a fairly 

 sharp tip, and this tip had an upward turn in the Blue whales, but this 

 was very slight in two of the specimens. In many of the whales the 

 fins had various small irregular notches round the tip. These appear to 

 be injuries, although it is hard to say what could have caused them. 

 In one case a larger notch was noticed at the base of the dorsal fin. 



The dorsal fin of Balcenoptera sibbaldii was found to be more pointed 



