366 



PROF. A. H. GARROD ON THE 



[Apr. 1, 



the continuity of the lower edge of the antepenultimate ring to a small 

 extent. The last tracheal ring is characterized by the great obli- 

 quity of the plane of each of its lateral moieties, the downturned angle 

 between which is less than 45°. Behind there is a considerable in- 

 terval between its downward-directed ends, filled up by the pessulus, 

 which is prevented from touching them by the intrusion of the ex- 

 tremities of the similar parts of the, also incomplete, penultimate 

 ring. In front the middle of the ring is expanded into a large, 

 quadrilateral, square-set cartilage, ossified in the adult, from the 

 superior angles of which the slender oblique side elements of the 

 ring take origin, to the inferior angles of which the first bronchial 

 semiring is articulated in the chick and consolidated in the adult ; 



Fig. 15. 



Fig. 16. 



Front view. 



Back view. 



Thaumalea picta. 



the middle of the superior margin of which also articulates or blends 

 with (according to the age) the broad median descending process of 

 the penultimate ring. The first and second bronchial semirings are 

 much alike ; both are slightly swollen at their extremities, especially 

 the anterior ; and their planes of direction are parallel, which is not 

 the case in Evplocamus. The lateral intervals between the penul- 

 timate and last tracheal rings are like the section of a plano-concave 

 lens with the concavity (formed as it is by the arch of the lateral 

 moiety of the last ring) downwards. The interval between the last 

 ring and the first bronchial semiring is considerable and broadly 

 fusiform ; that between the first and second semiring is narrow and 

 lanceolate, or fusiform in the adult, where the two semirings con- 

 solidate at their extremities. 



