PROGKESS OF MICROSCOPICAL SCIENCE. 243 



A Special Mode of Development in Batrachia. — In a late number of 

 the ' Academy ' appeared a notice of some importance on this subject. 

 It says that in a letter printed in the ' Kevue Scieutifique,' M. Jules 

 Garnier communicates some remarkable observations that have been 

 made by M. Baray on certain Hylodes which exist in large numbers 

 in the ish^nd of Guadaloupe. These animals are widely distributed 

 over the island, being found not only near the sea, but in the higher 

 lands of the interior, and after rain their ci'oak makes the air resonant. 

 The physical features of Guadaloupe, a volcanic island, the soil of 

 which is com2)osed of tufa, pozzuolana, and similar material, are so 

 peculiar and so very unfavourable for the maintenance of tadpole life, 

 which is essentially piscine, that M. Baray was led to expect the 

 existence of some peculiarities of development. The ova were easily 

 procured, as they were everywhere present under moist leaves. No 

 tadpoles could be discovered, but many of the frogs were of an extra- 

 ordinarily minute size. The eggs were spherical, with a diameter of 

 from 3 to 4 millimetres, and were each provided with a small spheroidal 

 expansion resembling a hernia of the gelatinous mass through a pore 

 in the envelope. In the centre of the sphere the embryo was visible, 

 lying on a vitelline mass of a dirty white colour, and having a thin 

 body, a large head and four styliform members with a recurved tail. 

 When the egg was touched the embryo moved rapidly and changed 

 its position. A day later the embryo was perfect, with a tail as long 

 as the body, translucent and like that of a tadpole. The limbs 

 imme liately formed, and at the expiration of a few days little frogs of 

 a dark greyish brown colour, and without a vestige of a tail, escaped 

 from the egg. M. Baray's observations have established the following 

 facts : — (1) That this Hylodes Martinicensis commences life by a 

 rotatory movement of the future embryo. (2) The fully formed 

 embryo performs the rotatory movements more rapidly, but in a 

 horizontal plane. (3) The brauchia; make their appearance, and 

 again vanish sometime afterwards. (4) The larva in the ovum is 

 provided with a tail and limbs. (5) The tail of the larva not only 

 facilitates the movements of the imj)risoned auimal, but also aids 

 respiration by the numerous and minute vessels which ramify in this 

 highly develojied appendage. (6) The animal issues from the egg in 

 the form which it preserves throughout life. As M. Garnier observes, 

 these observations seem to constitixte a starting-point for a special 

 investigation of great importance, and have a close relation to the 

 question of the adaptability of sjiecies to surrounding conditions. It 

 may be asked in this case whether the frog has been created with 

 special modifications adapting it to live in an island destitute of 

 marshes, or has it in course of time acquired a new mode of develop- 

 ment enabling it to survive under the excej)tional conditions under 

 which it has been placed. 



Discovery of the Position of the Bees Sting. — Mr. A. S. Packard, jun., 

 makes the following observations in a late number of the ' American 

 Naturalist,' and as they have an important claim to priority of discovery,' 

 they deserve a place here. He says that in '' Siebold and KoUiker's 

 ' Journal of Scientific Zoology ' for July, 1872, containing an account 



