Wiedersheim (1887a, b; 1888) was the first to describe in 

 detail the nasal apparatus of tetraodontids, while its 

 systematic importance was first stressed by Bibron (see 

 Dumeril 1855), although an overemphasis on the nasal 

 apparatus has led to confusion. Dunker and Mohr (1931) 

 described the changes in the nasal tube in Chelonodon 

 with increasing body size, and Barnard (1927) showed 

 the variety of nasal organs in South African puffers, 

 while Le Danois (1959) illustrated it for an even larger 

 selection of tetraodontids. Inger (1953) illustrated the 

 differences in the olfactory epithelium between 

 Tetraodon kretamensis and Chelonodon fluviatilis. 



Chonerhinos and Xenopterus have the lateral line 

 more elaborately developed than in other tetraodontids, 

 with three lines on the body rather than only one or two. 



Figure 20S.~Canthiga8ter rostrata: lateral 

 view of pectoral girdle, composite based on 

 several specimens, 5.5.2-96.5 mm SL, Texas. 



while in Canthigaster the lateral line system is so in- 

 conspicuous that it can only be seen with the aid of 

 magnification. Nasal specializations also distinguish 

 these genera from other tetraodontids. In Chonerhinos 

 and Xenopterus (the Chonerhinidae of Fraser-Brunner) 

 the nasal apparatus is larger than in other tetra- 

 odontids, in the form of a large, low open cup with 

 numerous lamellae or folds, while in Canthigaster (the 

 Canthigasteridae of Fraser-Brunner) the nasal apparatus 

 is much smaller than in other tetraodontids, in the form 

 of a small, low simple tube with a single opening. 



In other tetraodontids the nasal apparatus ranges from 

 an upright sac with two nostrils (in Lagocephalus, 

 Sphoeroides, Guentheridia, Amblyrhynchotes, Fugu, 

 and Torquigener, these being the Lagocephalidae of 

 Fraser-Brunner, except that for purposes of the present 

 discussion the genera are more finely split than as recog- 

 nized by Fraser-Brunner, and in Colomesus, the 

 Colomesidae of Fraser-Brunner) to a tube with a single 

 nostril or a bifid tentacle or a simple single flap (Ephip- 

 pion, Arothron, Monotreta, Chelonodon, Carino- 

 tetraodon, and Tetraodon, the Tetraodontidae of Fraser- 

 Brunner, except, as above, for purposes of the present 

 discussion, more finely split). While the lateral line 

 systems in Chonerhinos-Xenopterus and in Canthi- 

 gaster are each in their own way just as distinctive as 

 their nasal apparatuses, the situation is not so neatly 

 simple in the other tetraodontids. 



Among those genera with the relatively normal nasal 

 apparatus as an upright sac with two nostrils, 

 Sphoeroides and Guentheridia have a single lateral line 

 on the body, although short segments of an additional 

 lower line are sometimes present (see illustrations of S. 

 lobatus, S. dorsalis, and G. formosa), while in 

 Lagocephalus, Amblyrhynchotes, Fugu, Torquigener, 

 and Colomesus two lateral lines usually are present, the 



Figure 209.— Canthigaster 



roBtrata: lateral view of 



caudal fin supporting 



structures, composite based 



on several specimens. 



55.2-9G.5 mm SL, Texas. 



