372 Mr. C. T. Eegan on the Skeleton and 



Garden, Red House, Berkhamsted, Herts -.—HaplopJi- 

 thohnus danicus ; Trichotu'scus j^nsilhis and roseus ; Om'scus 

 aselhis ; Philoscia muscorum ; Platyarthrus Hoffmanseggii ; 

 Metoponorthus pruinosus] Porcellio scaber ; CyUsticus con- 

 vexus; ArmadiUidium vulgare. 



In my former paper at the bottom of p. 75 — in consequence 

 of a wandering mind, I suppose — the word '•^ Porcellidium '' is 

 suhstituted for ArmadiUidium. 



XLIX. — On the Skeleton and Systematic Position of 

 Luvarus imperialis. By C. Tate Regan, B.A. 



In a recent paper* I pointed out numerous resemblances 

 between Luvarus imperialis and the Acanthuridre. About a 

 month previously Mr. E. R. Waite t had published in 

 Australia an account of the skeleton of a large specimen 

 stranded at Bermagui, New South Wales — a fact of which I 

 could not have been aware when my own paper was written. 

 I have now had an opportunity of examining the skeleton 

 of one of these fishes taken in September last near St. Martin's 

 Point, Guernsey, and as a result I find that Luvarus must 

 be considered to be a most abnormal and specialized Scom- 

 broid, and that the features in which it approaches the 

 AcanthuridaB — the most notable of which are the restricted 

 gill-openings, united pelvic bones, small numbei of vertebrte, 

 short first vertebra, and maxillaries attached to the non- 

 protractile premaxillaries, as well as the correspondence in 

 the visceral anatomy — are to be regarded as the result of 

 convergence. Examination of a large and considerably 

 damaged specimen previously led me to believe that the 

 palatmes lacked the posterior (prefrontal) articulation ; but 

 in this I was evidently mistaken. 



In the skeleton now dealt with the anterior part of the 

 skull has been cojisiderably injured ; in other respects it is 

 vtry complete. Mr. l^oulenger has pointed out to me that 

 the Scombiic^se and Xiphiidse are remarkable in that the 

 deeply forked bases of the rays of the caudal fin are inserted 

 nearly vertically and extend over the hypural so as to almost 

 entirely conceal that bone, those of the upper and lower 

 series nearly meeting in the middle line on each side. Tiiis 



* Ann. & Mag. Nat. Hist. (7) x. 1002, p. 278. 

 t Hec. Austral. Miis. iv. 1902, p. -92, 



