268 



HARD WICKE ' S S CIENCE- G SSIP. 



sending off nerves to each pair of legs, and connected 

 together by commissures running down the length of 

 the body. 



The first step of the wasp surgery is to pierce the 

 membrane between the head and first segment of the 

 body and to sting the brain-like supra-oesophagal 

 ganglia of the head, or the commissure cords that 

 connect them with the body in general. This, if we 

 may trust our imperfect human notions of the 

 physiology of the nervous system, is equivalent to the 

 administration of chloroform, as it disconnects the 

 body with the machinery of sensory consciousness. 

 In higher animals it would produce general 

 paralysis, but not so in caterpillars, every segment 

 having its separate motor centre as above described. 

 The kicking and struggling due to these, although 

 rendered merely automatic, would by the first opera- 

 tion still be inconvenient, therefore this operation is 

 followed by eight others, one perforation and paraly- 

 sing at each pair of segmental ganglia ; thus paraly- 

 sing each pair of legs and permitting the young wasp 

 to feed upon the caterpillar segment by segment, 

 without inconvenience, either to the feeder or the food 

 which remains alive, though quiescent up to the last 

 morsel, by virtue of its semi-independent segmenta- 

 tion. 



There is another species of wasp, to which I have 

 not been introduced by name, which is carnivorous 

 in its adult stage. This feeds on an animal in which 

 the nervous system is more centralised than in the 

 caterpillar, viz., on a grasshopper, the carcass of 

 which is preserved by a single operation that is per- 

 formed by throwing the grasshopper on its back, 

 bending back its head so as to open the articulation at 

 the neck, and then piercing the membrane and 

 crushing the supra-cesophagal ganglia by a squeeze of 

 powerful jaws. Paralysis and insensibility are thus at 

 once produced without destroying the thoracic and 

 abdominal nervous machinery which controls the 

 functions of respiration and nutrition. 



Thus a living but insensible carcass is stored in the 

 larder, one that may be eaten at once or kept in good 

 condition, or even fattened by administering an easily 

 digestible, nutritious syrup that the wasp collects 

 for the purpose ; none of its working energy is 

 dissipated in supplying the grasshopper with saltatory 

 or other muscular force ; all is economised to do the 

 work of nutrition. 



Cat Day at the British Association. — 

 "Every dog has his day," in the ordinary course of 

 nature, but at the British Association, September 7th 

 of this year was largely devoted to cats by the Zoo- 

 logical Section, the chief subject being the heredity 

 of their abnormal toes. Mr. E. B. Poulton described 

 a kitten sent to him from Wales in 1879 with six 

 toes on each foot. The mother of this kitten had 

 seven toes on each of the fore feet ; thus mother and 

 kitten both had twenty-four toes, though not similarly 



distributed. Then Mr. Poulton's kitten became 

 frequently a mother, her husbands being ordinary 

 twenty-toed cats ; nevertheless in many of her 

 families ' ' a high percentage of abnormality occurred." 

 One kitten with five toes on the fore feet and six 

 on the hind was given to a friend, which "among 

 many families with a high proportion of abnormality, 

 produced a kitten with seven toes on the fore feet 

 and six on the hind, thus reverting to the condition of 

 the great-grand-parent in the possession of Mr. 

 Yaughan " who gave Mr. Poulton his first kitten. 

 This multiplication of toes is still proceeding among 

 the cousins and nephews and nieces, and later 

 generations. 



Miss Lydia Becker described a Suffolk cat with 

 abnormal toes, and others joined in the discussion, 

 all agreeing that the phenomena are very interesting, 

 but nobody appears to have suggested the appoint- 

 ment of a cat committee to investigate experimentally 

 and report annually on the subject of such heredity. 



Many years ago — when I was a boy — there lived 

 in Wardour Street, Soho, a pork butcher named 

 Foot, whose children all had supernumerary toes, and 

 were objects of considerable interest in the neighbour- 

 hood. We had an old black servant at the time, and 

 I well remember her explanation. Mr. Foot dealt 

 largely in boiled " pigs' trotters," i.e. feet ; these were 

 displayed in the shop window, arranged in a row by 

 Mis. Foot, who served the customers. Black Polly 

 maintained that the contemplation and handling of so 

 many toes by the mother caused the evolution of her 

 children's abnormality — she expressed her theory, 

 however, in somewhat different terms. 



The Height of Waves. — Some curious ex- 

 aggerations have prevailed concerning this subject, 

 and many have been the controversies relating to it. A 

 captain in the mercantile marine, writing to'the "Liver- 

 pool Mercury," describes his investigations, which 

 appear to have been carefully conducted by viewing, 

 while rounding Cape Horn, the waves that came up 

 astern from the mainmast in a line of sight to the 

 horizon, and marking on the mast the height of co- 

 incidence. On measuring the distance from these 

 marks to the mean draught, he found them to be as 

 follows : 64, 61, 58 and 65 feet in height, and that the 

 length of the waves varied from 750 to 800 feet. 



Ansted says : " The highest and largest waves do 

 not often exceed forty feet from the crest to the 

 deepest part of the trough," and adds, "when these 

 great waves approach the shore or shoal water, and 

 reach the bottom of the sea they increase in height, 

 reaching sometimes to upwards of 150 feet, but they 

 diminish in breadth or amplitude, and become 

 pointed." 



The difficulty of determining the height of waves 

 from a ship is very considerable owing to the insta- 

 bility of the platform on which the observer stands, 

 while the measurement from the shore is easy enough. 



