348 82 



nearly in contact with the notochord by their proximal ends, are pushed farther out and 

 become apposed upon and interposed between the spinous dorsal radii springing directly 

 t'roni three vertebræ. " 



Mc. Mlkiuch describes and figures (3-1, p. ()48— 49, and PI. XLII, lig. 2) the developing inter- 

 spinous bones in the larval Syngnatliiis [XTkianiis as cartilaginous rays, resting directly on 

 the membrane surrounding the spinal cord ": in later stages 1. c. fig. 6) they are said to be 

 united distally by a longitudinal bar, resting on which are cartilaginous nodules (i. e. the 

 distal interspinous segment of the adult), each supporting a fin-ray. The urostylic cartilages 

 for the, at first heterocercal, tail-fin are large and may be compared to the interspinous rays 

 of the dorsal tin. The anal fin (.the interspinous rays of which are not mentioned or figured) 

 is, wrongly, stated to atrophy in the adult. 



\A\AJV.W)V.r, (32, p. 449) gives the number of vertebra- in Siphoitosioma lyphtc as 52—05. 

 of which the anterior 17—18 are abdominal. "The two first are modified and longer than the 

 remaining, strongly coalesced, the bonier between their neural arches having disappeared, 

 and serving as attachment for the shoulder-girdle. To this end the transverse processes of 

 the first vertebra are very much expanded, giving strong and immovable attachment to the 

 upper ends of the clavicles. Also the transverse processes of the second are somewhat 

 expanded, and their ends are attached to the clavicles, where the latter are bent. Otherwise 

 the vertebræ in general have transverse processes, to the end of which the plate-rings are 

 fastened. These processes are longest on the abdominal vertebræ and generally truncated. 

 The spinous processes are low, laterally compressed and plate-sha])ed, only little or not at 

 all separated, and show a series of several rods -connected by thin lamellæ. The anterior 

 caudal vertebræ, which support the dorsal fin, have the spinous processes somewhat more 

 elevated, and with 3—4 free points, to which the interspinous bones of this fin are attached. 

 Ribs are wanting." 



Smitt 54), who has so admirably interpreted the suspensory parts of the head-skeleton 

 which are by no means so easy to make out as the vertebræ, only says regarding the latter 

 (p. 666i, that they are but slightly ossified, elongated, "the iirocesses straight and of uniform 

 breadth or slightly broader at the top; but in the vertebræ above which the dorsal fin is 

 attached, the upper spinous processes are divided sagitally (in the longitudinal direction of 

 the body) into three or four divergent branches. Distinct hæmal arches appear only at the 

 beginning of the caudal region, where a few may be found." Thus it does not seem clear, 

 if Smitt has observed the interspinous bones or not. 



Biuu(;i-: v5, p. 578) describes at length the 34 interspinous bones in Siphonostonui tijphlc 

 and mentions briefiy those of Hippocampus yiillnlalu.s. He points out their bisegmental 

 structure, the distal segment being rejjresented by a cartilaginous nodule, and says that in 

 Siphonosloma they exhibit "a slight tendency to become arranged in groups of four each. 

 In each group the segments converge slightly towards their proximal ends, where they are 

 firmly attached to the summit of the neural arch of a subjacent vertebra. Distally the seg- 

 ments diverge slightly and their dorsal extremities expanding somewhat come into apposition, 

 and form with one another a continuous jieripheral margin." Into the bony structures, which 

 build up the latter, he does not enter, nor has he any remarks regarding the structure of the 

 supporting vertebræ. 



Jordan and Evi:rmann (21 a, p. 759) in their diagnosis of the order Lophobranchii adopt 

 the remarks of Cope, quoted above; the same are repeated in later works, by Jordan and 

 Snydeh (22, p. 3) and Jordan and Evermann (21 b, p. 117). 



HuoT (19, p. 252) remarks : "Dans la région du corps où se trouve la nageoire dorsale, 

 tes apophyses épineuses se prolongent par des cartilages interépineux qui, eux-mêmes, se 

 prolongent par les rayons cartilagineux(!) des nageoires", which mode of stating the facts is 



■ These cartilaginous rods are according to Mc. M.'s figure 2, as weil as ray own observations in 

 Siphonosloma tgphle and Syngn. rostellatiis, parallel to each other, as are the interspinous bones in 

 most adult bony fisfies. 



