EPHYDRIIXffi. 109 



chyma of the leaves of Lemna, on Alisma plantayo, etc.; those 

 of Pelina, Parydra and Ephydra in water. Of especial in- 

 terest are the habits of the larvae of various Ephydrce, as the 

 following account related to the writer by Prof. W. H. Brewer 

 will show : " The waters of Lake Mono are clear, very heavy, 

 have a nauseous taste, and when still the lake has a look as 

 of oil and is not easily disturbed. The water feel slippery to 

 the touch, and will wash grease from the hands or from clothes 

 cold, more readily than common soap-suds will when hot. It 

 is said that no fish or reptile lives in it, but it swarms with 

 countless millions of larvae that develop into flies which rest 

 upon the surface of the water, as well as cover everything on 

 the immediate shore. The numbers and quantities of these 

 flies and larvae are absolutely incredible. They drift up in 

 heaps along the shore and hundreds of bushels could be col- 

 lected. They only grow at certain seasons of the year, and 

 then Indians come from far and near to gather them for food. 

 The larvae or pupae are dried in the sun, the shell rubbed off by 

 hand, when a yellowish kernel (pupa) like a small yellowish 

 grain of rice appears. This is oily, very nutritious, and not 

 unpleasant to the taste, and under the name of koo-chah-bee 

 (so pronounced) forms a very important article of food. The 

 Indians gave me some of it; it does not taste badly, and, if 

 one were ignorant of its origin, it would make nice soup." 



Another species, Ephydra hians, is found in equally great 

 quantities in Lake Texcoco, near the city of Mexico, and Pro- 

 fessor Penafiel has given the writer the following notes con- 

 cerning them : 



" It is of the eggs of this insect that the greater part of 

 what is known as Ahuatle is composed and which is now used 

 by the natives, who have preserved the customs of the ancient 

 Aztecs. The eggs are cleaned and ground into flour, and are 

 prepared by mixing with hen's eggs and fried with fat into 

 small cakes. The larvae are also used for fcod under the 

 name of Pitxi." 



