IX PELOMEDUSIDAE CIIELYDIDAE 399 



etc., the eggs are heaped up for five days and \\\vn Nvorked. The 

 fluid oil for lighting is made from fresh eggs, which are put into 

 a boat and then trampled out with tlie feet. The oil is drawn 

 off into large earthen jars and put on the fire. Then it is rapidly 

 cooled. The best oil, used for frying fish, is that which is gained 

 from the roasted tortoises themselves. Fresli eggs are either 

 fried or taken with sugar, or mixed with nianioca-flour and water. 

 The young, which are hatched in -lanuary, arc likewise eaten 

 fried, or they are preserved in the fat of the parents. 



An average tortoise yields 5 lbs. of fat, costing on the spot 

 two mjlreis. The wdiole full-grown animal, of one yard in length, 

 costs the same, and its meat is suflicient to sustain a family 

 of six people for three days. To make 24 lbs. of oil reipiires 

 3000 eggs. Two or three tortoises would yield the same amount 

 from their fat. Consequently the destruction of the eggs causes 

 an enormous waste, and is after all tlic least economical pro- 

 cedure. In the year 1719, 192,000 lbs. were exported from 

 the Alto Amazones, representing 24,000,000 eggs. In 1700 

 there were still plenty of tortoises 50 leagues above the mouth 

 of the Para river. Now there is no assembly of more than 

 flfteen tortoises to be found anywhere within 300 leagues from 

 Para to the mouth of the Eio Negro. On the Eio Madeira, from 

 the mouth to the first cataract, 186 leagues distance, there are 

 now only two regular nesting localities. The upper Solimoes 

 and the Eio Yapura are still rich. Near Ega are regidar 

 tortoise-ponds, called " curral," which yield sufficient support t( > 

 their owners; the animals are fed with manioca - flour and 

 leguminous plants. 



Fam. 2. Chelydidae. — The neck bends under the margin of 

 the carapace, but remains partly exposed. The nuchal shield 

 is absent except in two Northern Australian species. There are 

 twelve pairs of marginal shields. The plastron is composed of nine 

 plates, and is covered with thirteen shields, one of wdiich is the 

 conspicuous intergular. The temporal region of the skull shows 

 great diversity. It is quite open in Chelodina, covered in by 

 broad expansions of tlie parietal bones in Flatemys, Emydura, 

 and Elscya, or bridged over l)y a parieto-squamosal arch, which is 

 very slender in Bhinemys, strong in Chelys and Hydraspis. The 

 palatine 1)ones are separated by the vomer ; the nasals are variable, 

 mostly present, but the prefrontals are always small, and separated 



