THE EVIDENCE OF THE OLFACTORY APPARATUS 



223 



In order to convey to my readers the antennae-like character of the 

 carnerostome in Galeodes (Fig. 101), and its position, I give a figure 

 (Fig. 94) of the organ from its dorsal aspect, after removal of the 

 cheliceras and their muscles. A side view of the same organ is given 

 in Fig. 95 to show the feathered termination of the carnerostome, 

 and the position of the dependent accessory portion {1.1.) (Crone- 

 berg's ' untere Anhang ') with its single long antenna-like feather. 

 In both figures the alimentary canal (al.) is seen issuing from the 

 conjoined supra- and infra-cesophageal mass. 



As is seen in the figures, the bilateral character of the rostrum, as 

 Croneberg calls it, is apparent not only in its feathered extremity 

 but also in its chitinous covering, the softer median dorsal part (left 



p"er\t 



Fig. 95. — Lateral View of Brain and Camerostome of Galeodes. 



gl. supr. ces., supra-oesophageal ganglion; gl. infr. ces., infra-cesophageal ganglion. 

 The rest of the lettering same as in Fig. 94. 



white in figure) being bounded by two lateral plates of hard chitin, 

 which meet in the middle line near the extremity of the organ. In 

 all the members of the scorpion group, as is clearly shown in Crone- 

 berg's figures, the rostrum or carnerostome is built up on the same 

 plan as in Galeodes, though the antenna-like character may not be 

 so evident. 



When we consider that the first pair of antennae in the crustaceans 

 are olfactory in function, Croneberg's observations amount to this — 



In the arachnids and their allies the first pair of antennae form 

 a pre-oral passage or tube, olfactory in function ; the small mouth, 

 which opens directly into the pharynx, being situated at the end 

 of this olfactory passage. 



