72 



SCIENCE 



[Vol. IV., No. 76. 



acter of the double refraction of biaxial minerals can 

 be determined, it is impossible to distinguish with 

 certainty between bronzite and hypersthene. 



PUBLIC AND PRIVATE INSTITUTIONS. 



Johns Hopkins university. 



Physical laboratory. — During the past year, origi- 

 nal investigations have been carried on, on the photog- 

 raphy of the spectrum by the concave grating, the 

 variation of the magnetic permeability with change 

 of temperature, the distribution of heat in the solar 

 spectrum, the determination of the B. A. unit of 

 electrical resistance in absolute measure, and the 

 determination of the specific resistance of mercury; 

 and experiments have been carried on, under the 

 direction of Professor Kowland, with an appropria- 

 tion from the government of the United States, with 

 the view to aid in establishing an international unit 

 of resistance. 



Chemical laboratory. — The following investigations 

 have been completed during the year: a contribution 

 to the history of active oxygen, the action of heat on 

 ethylene, the chemical conduct of the sulphinide 

 obtained by oxidizing a naphthaline-sulphamide, the 

 effect of light on fermentation, and the relative stabil- 

 ity of halogen derivatives of carbon compounds. 



Biological laboratory. — During the year, original 

 investigations, the results of which either have been 



or soon will be published, have been made in the fol- 

 lowing subjects: the nature of the process of the 

 coagulation of blood; the chemical composition of 

 the blood of the terrapin; the influence of various 

 salts and other substances on the contraction of the 

 arterioles; the suction-pump action of the heart; the 

 influence of sudden variations of arterial pressure 

 on the rhythm of the heart ; the action of carbolic 

 acid on the heart, and its antagonism by atropine; 

 the influence of convallarin and convallamarin on the 

 heart; the anatomy of Nemertians; the development 

 and metamorphosis of various insects; the develop- 

 ment and histology of Salpa; and the histology of 

 Amiurus. 



Marine laboratory. — During the summer of 1883, 

 the seaside zoological laboratory for the study of 

 forms of marine life was open at Hampton, Va., 

 from May 1 until Sept. 29. The advanced work 

 included original investigations on the following 

 subjects: the anatomy and development of barnacles, 

 the anatomy and development of crabs, the histology 

 of Eudendrium, the anatomy and development of 

 Balanoglossus, the development of the oyster, the 

 anatomy of Lingula, the protozoea stage of crabs, the 

 development of annelids, the anatomy and develop- 

 ment of Chrysaora, the origin of the eggs of hybrids 

 and tunicates, the function of the semicircular canals 

 of sharks, and the general zoology of the Hydrome- 

 dusae. 



RECENT PROCEEDINGS OF SCIENTIFIC SOCIETIES. 



Trenton natural-history society^ 



July 8. — Dr. C. C. Abbott remarked on the spade- 

 foot hermit-toad, Scaphiopus solitarius, the least com- 

 mon of the batrachians. Their appearance after 

 long intervals seems characteristic. The speaker ob- 

 served them in 1874, and not again until April 10, 

 1884. By the 15th, the weather becoming cooler, they 

 departed. On the afternoon of June 26, after a severe 

 storm, they became abundant in the same pond. The 

 eggs are deposited about submerged objects, hatch- 

 ing in six days ; the tadpoles growing rapidly, and the 

 young toads leaving the water in two or three weeks. 

 Like true frogs, this terrestrial batrachian can prob- 

 ably thrive fairly well in water. The creature's vocal 

 powers are terrific. The sound has been compared 

 to that produced by a heavily loaded, creaking wagon, 

 rolling over hard and uneven ground, and to the 

 groans of agonizing pain. Travellers on the highway 

 an eighth of a mile distant, listened in amazement; 

 and a ploughman was compelled to considerably 

 shorten his furrows, as the mules refused to approach 

 the source of the horrible yells. With the sound, a 

 protuberance nearly the animal's size appears beneath 

 the throat and belly, gradually decreasing with the 

 emission of the cry, but not entirely disappearing. 

 It lives in holes about six inches deep, dug by itself, 

 never entering the water except at the breeding-sea- 



son. At the bottom of the pit it seizes such insects 

 as enter, and probably seeks food by nocturnal wander- 

 ing. The burrows, which it forms by throwing the 

 earth to both sides by the assistance of the spur-like 

 projection on each hind-foot, have a smooth, some- 

 what tortuous, tubular entrance, oval in outline, and 

 sufficiently large to allow of egress : the toad sitting 

 in a chamber so placed that it would seem impossible 

 for it to leap out, as De Kay suggests, when food ap- 

 pears about the orifice at the surface. Indeed, tun- 

 nels made in confinement were always angular; and 

 it would be impossible for the animal to see an insect 

 at the opening. The toad, therefore, probably leaves 



the hole, and seeks food at night. Mr. William 



Macfarland detailed his experiments on the building- 

 habits of the basket- worm, Thyridopteryx ephemerae- 

 formis. If the full-grown larva is removed from the 

 case, it will not rebuild. But this is not so with the 

 young worm : an individual about two-thirds grown 

 had rebuilt five. times. The worm creeps under a 

 leaf, enclosing itself by drawing the edges together 

 with threads of silk. The leaf is then cut loose, the 

 larva adding bits of sticks as the case is dragged 

 about. Dr. A. C. Stokes presented a communica- 

 tion on the liver of the house-fly, with dissections. 

 The organ consists of two sets of tubules, originating 

 in sub-spherical bulbs, and uniting to form two tubes 

 opening on opposite sides of the intestine behind the 



