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It is with some diffidence that I refer the specimen at hand to the present species. 

 Three species have been described with the lateral margins of the carapace entire and unarmed 

 or nearly so, viz. L. integra (Miers), L. subintegra (Lanchester) and L. ijiermis Borradaile i). 

 The latter may be easily distinguished by the carapace being almost square, smooth, hairless 

 and microscopically pitted, but as to the remaining species, which both are covered with a 

 short, dense fur, it is not at all certain whether they are really distinct. Laurie -), who records 

 L. infe<rra from the Red Sea, apparently does not accept Lanchester's species and Bouvier ») 

 identifying a specimen from Mauritius with Miers' species, mentions Borradaile's view *) about 

 the distinctness of the two forms, but does not venture to express any definite opinion about 

 the question. 



Unfortunately the information of Miers") about his "Carchioplax'' ifitegra is not very 

 exhaustive, and about one important point, viz. the ratio of the length of the carapace to its 

 breadth, there is a discrepancy, as Laurie rightly puts forth, betw^een text and figure, the former 

 giving this ratio as i : 1.25 and the latter as i : 1.5. Leaving this aside, Bouvier describes a 

 specimen of exactly the same dimensions as those of Miers, and most likely identical with the 

 species, as being provided on the hepatic regions with sharp granules, projecting in an irregular 

 way beyond the outline of the carapace. 



Borradaile, who records L. Integra from Hulule, Male Atoll, enumerates the following 

 points, by which L. sudintegra is distinguished: three, instead of two, faint notches, on the 

 antero-lateral margin, external orbital angle almost right, not obtuse, front narrower. 



Taking as base Miers' figure, which is probably reliable, and with which both L.\urie's 

 and Bouvier's examples are expressly stated to agree completely, the specimen of the "Siboga" 

 is certainly not identical with L. integra, for the ratio of the length of the carapace to its 

 breadth varies, according to Miers and L.\urie, between i : 1.5 — 1.4, so that the carapace is 

 decidedly broader than in my specimen (length to breadth as i : 1.32, viz. exactly the same 

 as in de M.\n's specimen ^) which is identified by Lanchester with L. submtegrd). The width of 

 the fronto-orbital border is also greater than in the five specimens of Laurie (0.83 of the 

 greatest breadth in my specimen, and only 0.7 in those of Laurie). 



The whole carapace is densely covered with a short fur, but, when this is removed, 

 there is nothmg to be seen of the sharp granules on the hepatic regions, as mentioned by 

 Bouvier in L. Integra ; indeed the carapace is everywhere entirely smooth. The lateral margins are 

 little arched, and provided in their anterior part with three extremely-minute angles, which hardly 

 can be called prominences, the anterior of which, however, is by far the most distinct '). The 

 front is distinctly bilobed and measures 0.44 of the greatest breadth of the carapace (nearly 



1) Fauna and Geography Maldive and Laccadive Arch., v. i, 1903, p. 430, textfig. iii. Hab. Hulule, Male AtoU. 



2) Joum. Linn. Soc. London, v. 31, 1915, p. 464. 



3) Bull. sc. France et Belgique, v. 48, 1915, p. 119. 



4) L. c, p. 430. 



5) Zool. H.M.S. "Alert", 1884, p. 543, pi. 48, f. C. 



6) From Lanchester's measurements it results, that here the ratio is respectively i : 1.4, , : ,.24, , : ,.25 and 1 : 1.25. Save 

 in the first instance, which rather points to Z. integra, this ratio better agrees with those found by de Man- and by myself. 



,r. .. 1 ^■'''™^,f =■' "^S"'" "'^^^ "°"=''" ^' ^^^l' antero-lateral margin of the carapace, thus marking off four lobe-like teeth, which 

 are scarcely or not all prominent, and the margins themselves are much much more strongly arched. 



28 



