NATURAL HISTORY OF AMERICAN LOBSTER. 



335 



cord, motor and sensory elements, as well as the complex stomato-gastric system, have 

 essentially the same relations as are found in an adult animal. 



Natural food of the larva.— It is not to be doubted that the incessant activity of this 

 larva, which apparently knows no rest day or night, is needed, as Mead remarks to 



Fig. 40.— Swimming attitudes of young lobsters in the first free stages; a, lobster swimming with body bent in the 

 usual quadrant form, the head directed downward and often at a greater angle; the sw immin g branches (and the perma- 

 nent limbs rather more than here shown) directed backward, in "posterior" position of Hadley; resulting movement 

 upward and backward; b, young lobster playing caimibal, swimm in g astride the carcass of another, which it has nipped 

 at the junction of the carapace and abdomen and holds with its prehensile legs; c, sw immin g with the thoracic legs 

 directed forward; in "anterior" position of Hadley; resulting movement upward and forward; d, rising position 

 occasionally assumed; e, slowly moving or "floating" position sometimes observed; /, lobster "standing on head," 

 apparently probing the bottom with rostrum, but really too weak to rise. 



bring them into contact with the minute suspended bodies upon which they feed. All 

 the rearing experiments that have been conducted by Mead and others with any degree 

 of success during the past 15 or 20 years, whether in Europe or the United States, have 

 clearlv shown that the larvae must have their food suspended and in fine particles; the 



