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44 



hones which hear spinous rays. All (he succeeding interspinous hones, as also 

 those of the anal lin, are "hisegmented" ; there is, namely, at their distal cartila- 

 ginous ends an independent cartilage with an osseous centre; this segment is 

 embraced by the basal part of the ray. The rays are 

 composed of two lateral halves, articulated but not bran- 

 ched. These interspinous bones show nothing of special 

 interejl; they are formed like ordinary interspinous bones 

 and are for the most part grouped in i)airs between two 

 spinous processes (some variation in this regard occurs in 

 different specimens). 



The same holds good for the interspinous bones 

 of the anal fin; the first of these is the largest and is 

 placed behind the long hæmal spine of the first caudal 

 vertebra". 



The most frequent number of rays I find to be the 

 following: D,: 12; C: n + 4-|- 5 -I- n'; A: 19-20. (n often 

 = 6, n' often = 8). It is remarkable that the long rays 

 in the caudal fin agree with the number and grouping of 

 those in Amphisile; they are articulated as in that genus, 

 whilst the shortest of the small marginal rays are unarti- 

 culated. 



Cranial skeleton (PI. II, fig. 2 and text-figs. 25 -29). 

 The head has a similar appearance to that of Am- 

 phisile but is less compressed and the lower margin of 

 the preoperculum is not developed to a thin, transparent 

 plate. Regarding the skull from above (fig. 25) more of 

 the separate bones can be seen than was the case in Am- 

 phisile, as the posterior part of the skull especially is here 

 less compressed: namely: supraoccipital (so), epiotic {ep) 

 (posltemporal or suprascapular pt), pterotic (squamosum) 

 isq), frontals {fr), a quite small part of the poslfrontals 

 and prefrontals (pr/^, mesethmoid (mes) as also the vomer 

 (vo); in addition, the nasals (na) and preorbitals (ao). 

 As in Amphisile the parietals and opisthotics are wanting. 

 In front the supraoccipital meets the frontals, between 

 which it sends in a fairly long process; posteriorly it runs 

 out into a fairly large process, which as in Amphisile is 

 connected by a ligament with the first interspinous bone. 

 The frontals do not reach so far forward at their anterior ends as in Amphisile. 

 The mesethmoid (as in the figure) may appear between the frontals and the nasals 

 with a quite small part, then be covered by the latter, appearing again as a short, 

 slightly broader piece between the nasals and behind the vomer. The posttemporal 



Fig. 25. 



Crnli-isriis scolopax. Skull, seen 

 Irom aliiivr. so: supraoccipi- 

 tal; t'p : cpiiitic: pt: posllcm- 

 poral; sq: ptcrolic; /r: IVonlal; 

 prf: prdVonlal : «o; aiilorl)!- 

 lal ; mes: niesclhnioid; na: na- 

 sal ; im : vomer. 



