480 The Animal Kingdom 



cellent coordination of movements is assured by variation in nerve fiber 

 diameter : giant fibers pass to the more remote parts of the body, 

 slender ones pass to portions nearer the "brain." The eyes form a 

 real image which, however, is not inverted as in the vertebrate eye. 

 Statocysts for equilibrium are located below the "brain." 



The sexes are separate among the squids, and mating is often 

 preceded by some courtship activity in which spernmfophores (a bundle 

 containing many sperm) are transferred by the male into the mantle 

 cavity of the female. These are transferred from the vas deferens by 

 means of one of the arms of the male which is modified for just that pur- 

 pose. The eggs are deposited on the bottom within a few hours after 

 mating. The eggs are surrounded by a gelatinous mass which swells 

 up. This gelatine is apparently inedible for most animals and also 

 immune to fungus growths ; thus the developing squids get considerable 

 protection. They hatch within thirty days of being laid and there are 

 no intervening larval stages. 



Other Squids. — The squids are tremendously abundant animals 

 throughout all the ocean waters, ranging from the shallows to the abyss.' 

 In size, they range from a tiny iy2 inches to giant ones which have 

 an over-all length of 55 feet. One squid found ofif Newfoundland was 

 of this latter size and had a body 20 feet long and 3^ feet in diameter, 

 or 12 feet in circumference. It would have weighed nearly 30 tons! 

 Certainly these are the mightiest of the invertebrates. The extreme sizes 

 which these giant squids can attain are not known, and this particular 

 specimen may have been only a medium-sized one. Some of the deep-sea 

 squids have their bodies covered with tiny luminescent organs. The 

 abundance of these latter forms may be greatly underestimated inasmuch 

 as they move too rapidly to be caught in the slowly moving deep-sea 

 trawls. 



Other Gephalopods. — The octopuses have long excited the imag- 

 ination of sailors and land dwellers. Many tales of their powers have 

 been spun. Actually most species are small in size and quite harmless. 

 Most of them spend their time quietly among rocks with their strange 

 globose bodies surrounded by the eight sprawling arms. Although it 

 seems certain that the octopus, like the squid, can attain a large size, 

 there are few or no records to verify this. Some weighing 110 pounds, 

 which would have a radius (including the arms) of 10 feet, have been 

 observed. The octopuses have great powers of regeneration and may 

 grow new arms after they have been lost. The eggs are deposited 



