The Lateral Nasal Glands of Amphiuma. 155 



the other makes a few abrupt convolutions and then divides into three 

 subdivisions. Of these two are hardly more than simple, slightl;^ 

 convoluted tubules which have not more than half the length of the 

 third (and middle) division. The latter at about the middle of its 

 course becomes suddenly greatly complicated, showing convolutions, 

 distensions, longitudinal splitting, branching and alveolar swellings, 

 and is apparently dividing up into tlie anlagen of the lobes of the 

 posterior half of the adult gland, while the anterior half will be 

 formed from the other shorter branches. 



The left side of the same specimen possesses a glandular mass 

 equal in extent to that of the right side. This opens into the nasal 

 passage by three separate orifices, but, owing to the fact that the 

 series is somewhat imperfect, it is impossible to trace out the rela- 

 tionship of the individual tubules. 



A comparison of the above facts shows that the lateral nasal gland 

 and the nasal muscles with which it is associated are structures char- 

 acteristic of adult life. The gland makes its first appearance, as two 

 or three closely associated evaginations of the lateral wall of the 

 nasal cavity near the inner end of the introductory nasal passage, 

 while the muscles arise from the connective tissue underlying the 

 nasal epithelium immediately posterior to this point. 



. That the development of the tubules takes place with great rapidity 

 is shown, not so much by comparison of -the proportionate length of 

 the glandular mass in the successive stages studied, although this 

 comparison shows on the whole a gradual increase, as by the rapidly 

 increasing complexity of structure of the tubules. Moreover, one 

 of the tubules (the middle one when there are three) undergoes a 

 development so much more rapid and complicated than the others that 

 I shall designate it the main gland of the group. In its development 

 several distinct processes occur. The tubule shows an early tendency 

 to become convoluted, often making abrupt curves. Further, there is 

 much branching not only by the simple process of evagination, but 

 even more conmionly by the longitudinal splitting of a distended 

 portion of a tubule into two tubules which remain in communication 

 at one or more points. All of this branching seems to be in its details 

 quite irregular, although carrying out a certain underlying plan of 



