568 



édition française du »Lehrbuch der Anatomie des Menschen« de C. 

 Gegenbaur. Je ne pourrai les livrer à la publicité que dans le courant 

 du mois de Décembre ou de Janvier prochain. Je discuterai alors le 

 mémoire du Dr. Dohrn, en fournissant toutes preuves à l'appui de ma 

 manière de voir et en exposant les faits que j'ai observés. 

 Liège le 26 Juillet 1888. 



6. The Nest and Eggs of the Alligator: Alligator lucius Cuv. 



By Prof. Samuel F. Clarke, Williams College, Mass. U. S. 



eingeg. 28. Juli 1888. 



It is somewhat remarkable that so promising a field of inquiry as 

 that of reptilian embryology should have been so generally neglected ; 

 and it is certainly remarkable that almost nothing is known of the 

 development of the Crocodilia or Loricata, the largest and most highly 

 organised of the reptiles. The eggs and young alligators are such 

 common objects in the shop windows in many of the southern states 

 that it appeared to be a simple matter to secure the eggs at the right 

 time and in abundance. It proved on the contrary to be very difficult. 

 I was assured by various hunters in Florida that each month from 

 January to September inclusive was the only month in which the 

 alligators lay their eggs and this resulted in my having to make two 

 journeys of over twenty-six hundred miles each. 



At the time of my first visit, the first week in April us eggs had 

 been laid and the ovaries of adult female alligators were full of eggs 

 of all sizes up to 26 mm in diameter. I returned to Florida June 4 

 and found that I was still somewhat early as the nests were then being 

 built. With the aid of five experienced hunters I at last succeeded in 

 finding on the ninth of June a nest evidently just completed in which 

 there were twenty-nine eggs. The next day at a point forty miles 

 farther north a second nest was found with thirty-one eggs. 



There were many nests found old and new, but only these two 

 contained eggs. 



The nests vary much in size, the largest being about two and one 

 half metres in diameter at the base and eighty cm high in the central 

 part, the whole having the shape of a rounded cone : they are located 

 generally on a slightly elevated place which is higher by a metre, or 

 slightly more, than the surrounding level and covered Avith a thick 

 growth of palmettos, mangroves, magnolias etc. These are called 

 »hummocks« by the natives. On one side of the hummock at least, in 

 some cases on all sides, is a pond from one third to two metres in depth, 

 and in the bank, under the water the female alligator digs a cave which 



