14 NOTES AND COMMENTS [july 



the spider " does not stop to pull out the captives, wring their necks, 

 and throw them into a bag. It gathers up its net and postpones the 

 work of revision until it gets home." This interesting paper will be 

 found in Zoologischcs Jahrbuch, xii. (1899), pp. 161-169, 1 pi. and 1 fig. 



E pur si muove 



We could not find a finer instance of the progress of science — which 

 it is part of the function of our journal to record — than Dr. (now Sir) 

 J. Burdon Sanderson's Croonian Lecture, delivered to the Royal Society 

 of London on March 16," On the relation of motion in animals and 

 plants to the electrical phenomena which are associated with it." 



The progress to which we refer might be best indicated by a 

 summary of the actual results and suggestive hints to which the lecture 

 gives expression, but it seems more picturesque and not less important 

 to cite the first two paragraphs, for they indicate as it were graphically 

 the strides of modern physiology to which the baronet's genius has 

 given so much force. 



"Jn a Croonian Lecture which I delivered to the Eoyal Society in 

 1867 — more than thirty years ago — I exhibited a number of diagrams 

 of graphic records in evidence of the mechanical relations which I then 

 sought to establish between the movements of the heart and those of 

 respiration in the higher animals. 



" I have to-day to bring before you results which have also been 

 obtained by a graphic method, which however differs from the other in 

 that the records are written by light, and not by pen on paper ; that 

 the time taken in recording is measured in thousandths of seconds, not 

 tenths ; and finally, that the events recorded are not the movements of 

 the chest or heart, but the electrical changes which, as will be shown, 

 are found to associate themselves with all manifestations of functional 

 activity in living organisms, whenever these take place under conditions 

 which admit of their being investigated." 



A Complementary Male. 



Many years ago Darwin discovered a little creature living on the 

 barnacle, Scalpellum vulgarc, which he at first regarded as a parasite 

 and afterwards as a " complementary male." In other cases, as is well 

 known, he found a similar dimorphism, — minute complementary males 

 fixed to the hermaphrodite barnacles, and in some rare species to 

 females. Since Darwin's work there has been little if any re-investiga- 

 tion of the complementary male of Scalpellum vulgare, but it has recently 



