No. I.] THE EMBRYOLOGY OF LIMULUS. 37 



they frequently come so close to the shore that portions of the 

 carapax are uncovered. 



I have already commented upon the great vitality of the 

 eggs and the young ('85, p. 522), but a few words more may 

 prove of interest. When studying the development in 1884 the 

 eggs I studied were transported 200 miles from the place they 

 were laid. They were six days on the journey, packed in moist 

 sand, but without any addition of salt water. On August i I 

 left the shore, taking with me some 200 embryos and about a 

 pint of salt water. By merely supplying the loss by evapora- 

 tion with fresh water from the city supply I kept some of these 

 alive until November 20, when the last were killed to supply 

 material for study. In 1890 I fertilized some eggs on June 22. 

 Some 200 of these were taken in half a litre of water to Lin- 

 coln, Nebraska, 1600 miles from the shore, where they lived 

 from September 7 to the week of November 14-20, when they 

 were killed by an accidental drying up of the water during a 

 temporary absence. As it was, they lived over twenty weeks in 

 confinement. It would not have been possible to keep them 

 much longer, as the stock of food yolk was about exhausted. 

 Adult specimens have been shipped alive to San Francisco, 

 and now one meets occasionally with notices in the Pacific 

 coast papers of the capture of horse-shoe crabs, probably those 

 planted there several years ago by the U. S. Fish Commission. 

 They have also been shipped alive to England and Germany. 

 Professor E. Ray Lankester had three barrels of these animals 

 sent him in London from Woods Holl, a large proportion of 

 them surviving the voyage.^ 



An observation made by Dr. Lockwood upon the retardation 

 and vitality of the eggs should be repeated. He says ('70, pp. 

 271-272): "At the close of the warm season last year [1869] 

 my jars must have contained not less than 200 young Limuli. 

 . . . Hoping to continue observations upon the growth of my 

 interesting family, the jars were carefully put away. Little 

 regard, however, was paid to temperature, which, on several 

 occasions, went down to the freezing-point. On the 3d of May, 

 1870, I emptied the jars to see how my charge was getting on, 

 when lo ! not one of the last year's hatching was alive ! but, won- 



^ Mr. Vinal Edwards, who made the shipment, informs me that those packed with- 

 out seaweed or other moist packing survived the journey the best. 



