xxviii HISTORICAL INTRODUCTION 



The backward extension of the sternohyoid muscle to the pubis is 

 not associated with the extra length of the lungs, as suggested by 

 Haro (1840), but is due to the fact that there is no fixed sternum 

 as in the Frogs. The sternal region of the pectoral girdle in Sala- 

 mandra moves with the limbs, and therefore offers no point d'appui 

 which could serve for muscular attachment. In the following year 

 Panizza is engaged on an experimental investigation into the flow and 

 velocity of the respiratory current in the larva of the Salamander. He 

 describes the action of the cilia in directing and maintaining the 

 current, and examines the conditions which affect the vitality and 

 irritability of the ciliary mechanism. 



Duges's work on the osteology and myology of the Batrachia 

 (1834) includes some observations on the terrestrial Salamander. 

 The figures are good and accurate, but not accompanied by adequate 

 descriptions. The object of the paper is to compare the condition of 

 the skeleton and muscles of larva and adult. Some structures are 

 peculiar to the larva and others to the adult, but those which occur 

 in both undergo modification during metamorphosis. The figures 

 are the most detailed and accurate of these two systems so far pub- 

 lished, but the Urodeles have not been so carefully studied as the 

 Anura, and Triton figures much more largely in the paper than 

 Salamandra. Reichert's work of 1838 also relates to Triton, but it 

 is very important from the point of view of the development and 

 morphology of the skull and visceral arches in the Urodela. Henle 

 is the first author to investigate the anatomy of the larynx of Sala- 

 mandra, which he describes in a noteworthy and accurate work pub- 

 lished in 1839. 



We now reach the numerous and striking contributions to Sala- 

 mandra literature for which Rusconi is responsible. The first was 

 published in 1839, and the last, which was posthumous, in 1854. 

 Owing to the fact that Rusconi coloured the plates of his papers with 

 his own hands, and was unable or unwilling to devote the necessary 

 time to this task, several of his most important writings are very rare, 

 having been limited to editions of 100 copies, and in one case of only 

 24. In his first paper Rusconi states correctly that in S. maculosa the 

 sexes couple on land and not in water, and therefore the sperm 

 cannot reach the oviducts mingled with water as had hitherto been 

 accepted. He further denies (this time wrongly) that only two larvae 

 may be produced at a time in a Salamander, thus showing that he was 

 not aware of the difference in this respect between maculosa and atra. 

 In fact he declines to believe that there can be such a considerable 

 distinction between the species. He was greatly puzzled when he 



