322 Miscellaneous. 



" branchiform " stigmata. These " branchiform " stigmata he de- 

 fined * as " spiracula circularia, membrana braniformi eorrugata 

 intus vestita," and von Porath, in establishing the genus Otosfigma 

 (z=Branchiotrema, Kohlr.), also accepted this definition t. But 

 Kohlrausch J indicated that he could not find any resemblance 

 to branchiae in these stigmata, although he adhered to the 

 opinion that the stigmata are closed from -within by a branchiform 

 membrane. 



In working up the ludo-Australian Chilopoda, the results of which 

 I shall shortly publish in a larger memoir, I was led to investigate 

 the structure of the stigmata, which I studied particularly in tan- 

 gential sections. 



The simplest form is the apertural stigma, which occurs in Litho- 

 bins and Ilcnicops, and has been fully described by me §. It is 

 characterized by the undeveloped poritrema, by a rather short calyx, 

 lined within with a lattice-work of setae, and destitute of special pro- 

 tective apparatus, and by the cylindrical tracheae which open simply. 

 A similar form occurs in the young (foetus, Ltz.) of the Scolopen- 

 dridae, which, after quitting the egg, lie motionless for a consider- 

 able time, and are covered by the body of the mother, in Scolopendra 

 as well as in Heterostoma. Thus this simple form constitutes the 

 common starting-point of the fissiform and cribriform stigmata. 



In Crypiops the fundamental form is very distinctly marked, 

 while in Connocephnlus it already leads towards the stigma of the 

 true Scolopcndrce by the ' more fissiform and margined external 

 orifice, and by the accession of simple circlets of spines before the 

 opening of the tracheae. In the Scolopcndrce the stigmatic cavity is 

 divided into an exterior vestibule and the true calyx, and the cir- 

 clet of spines before the direct opening of the tracheae attains its 

 highest development. 



The ear-shaped ( = branchiform) stigma of Otostigma, v. Por., and 

 Branchiostoma, Newp., may be derived from the apertural stigma 

 by regarding the calyx as obliquely compressed for a small portion 

 of its length. On the floor of the stigma in these forms a few 

 irregular dark-coloured islands make their appearance, and these 

 are beset externally with the small booklets which are so frequent 

 in the stigmatic calicos of the Chilopoda. These islands are the 

 remains of the original floor of the stigma, while the clear straits 

 surrounding them are formed by the gradually flattened and dilated 

 debouching surfaces of tha^ tracheae. The external aperture of the 

 ear-shaped stigmata is round and finely denticulated at the margin ; 

 there is no projecting ring as in Scolojjendra. 



* Newport, "Monograph of the. . . .Chilopoda," Linn. Trans, vol. xix. 

 p. 411. 



t O. von Porath, Bihang till K. Sv. Vet.-Ak. Handl. Bd. iv. no. 7 

 (1876), p. 19. 



X Kohh'ausch, ' Beitrage zur Kenntniss der Scolopendriden ' (Mar- 

 burg, 1878j, p. G. 



§ E. Haase, "Das Respirationssysteni der Symphylen und Chilopo- 

 den," in Zool. Beitrage, Bd. i. p. 76 (Breslau, 1884). 



