ZOOLOGY. 

 The Limpet's Strength.— The experiments made l.y J. Law- 

 Fasting fleas on an average pull 149:; times their own dead weight. 

 Other experimenters give the pulling power of the shell-deprived 



Venus verrucosa of the Mediterranean, a cockle-like creature, at 2<>71 



times the weight of its own body. 



The force required to open an oyster appears to be 1319.5 times the 



weight of the shell-less oyster. (Nature, March 24, 1892). 



Dr. Steindachner has published the 15th part of his Ichthyologische 

 Beitriige 1 in which he describes the following species of South Ameri- 



Piabuca argentinia Lin. ; Iquitos. 

 Piabuca spilurm Gunther : liyavary. 



Bergia altipinnis sp. nov.; Arroyo Mignelete near Motevideo. 

 Tetragonopterm lineatus sp. nov. Iquitos. 



Tetragonopterus anomalus sp. nov. Rio Parana near Corrientes. 

 Xiphorhamphus jent/mii Giinther ; Arroyo Miqiielete and Parahyba. 

 Xiphorhamphm hepsetus Cuv.; Arroyo Miquelete and Parahyba. 



Medical and Other Opinions upon the Poisonous Nature 

 of the Bite of the Heloderma.— In North America there are two 

 species of Heloderms,— the Heloderma harridum of Wiegmann, a 

 form that does not occur within the limits of the United States, and 

 the Heloderma suspectum of Cope, which is found principally in suit- 

 able localities throughout Arizona. There this, the biggest by all odds 



the fact that it was once common on the Gila River. Collectors are 

 now rendering it scarce over nearly all its range, and no doubt the 

 time is not far distant, comparatively, when this highly interesting 

 species will meet with utter extinction. 



Living specimens of this reptile have been in the wn 

 for a year or two together, affording him admirable < 



