Page:Encyclopædia Britannica, Ninth Edition, v. 17.djvu/132

120 M Y R M Y R ambulatory legs, a second pair of rudimentary appendages lying in ternally to these latter. The legs are five-jointed and bear each a pair of claws as in Campodcn and Peripatus instead of a single claw as in other Myriapoda (Lithobius sometimes bears a pair on the anal legs only). There is a pair of caudal stylets on the last somite per forated by the ducts of silk glands. The arrangement of the stigmata is uncertain. Hasse finds only a single pair on the head, Wood Mason and others many pairs on the body so mites. Peculiar paired segmental organs are present on the ventral surface which may be excretory. It appears not impossible that Scolo pendrella may have originally pos sessed tvo pairs of appendages to each somite, and may thus represent to some extent a transition form be tween the ancient Diplopoda and the more recent Chilopodous type ; but as the anatomy of ScolopendreUn is as yet imperfectly known, and nothing isknown as to its embryonic development, its place in classifica tion must remain for the present an open question. By Ryder a sepa rate order (Symphyla) has been formed for it, whilst Packard has placed it amongst the Thysanura notwithstanding its numerous jointed legs, which constitute the most essential distinction of Myria- FlG - poda from Insecta. Remains of representatives of the Chilopoda have not been found in Paleozoic strata. The earliest known are Secondary from the Solenhofen slate. highly magnified (slightly modified from Packard) ; a, caudal stylets ; b, b, first post-cephalic append ages ; c, antennas ; 2, one of the functional legs further enlarged (from Wood Mason), showing the live joints and terminal pairof claws ; b, inner rudi mentary leg of same somite. Development of the Myriapoda. Scolopendra is viviparous like Perijmtus. Lithobius lays its eggs loosely amongst earth ; they are very hard to find there, and nothing is thus known of its development. The female Geophilus lays her eggs in heaps and watches over them ; in the case of Julus the process is similar. Information as to the develop ment of the Myriapoda gener ally is at present very imper fect. In no case as far as yet known is a blastopore formed as in Peripatus. The first struc ture to appear in Strongylo- soma (Polydesmidsi) is a ventral thickened plate. The append- Flo age:; are formed in succession from before backwards, and the mouth and anus as stomodsenm and proctodaeum. The embryo when hatched (fig. 14) has nine post-cephalic somites, the second of which is without appendages, whilst the first, third, and fourth each bear a functional pair of limbs, the fifth bears two pairs of rudimentary limbs be neath the larval skin, and the sixth a single pair, which very soon becomes double. The young Strongylosoma is thus provided with three pairs of functionally active legs. The young Julus has a similar number, the third post-cephalic somite being apodous, and it was formerly considered that this fact established a connexion between the Myriapoda and the Insecta, the three pairs of larval legs of the Myriapod being supposed to correspond with the three pairs of legs of insects. Such, however, is not the case ; there being no second maxillae in Myriapoda, the first pair of legs in the larva must correspond with the second maxilhe of insects ; and even if this could be shown to be incorrect, the three pairs of legs would still not corre- 14. Larva of Utrniigylnsoma (rue.rinii just hatched. (From Dalfour, after Metschnikoff.) spond with those of insects, because in the young Stron- yylosoma the second and in Julus the third post-cephalic somites are devoid of legs. Moreover, the larvse are only apparently hexapodous, not in reality so. In Pauropus there is a hexapodous larval stage. In the Chilopoda no functional or real hexapodous larval stage occurs, as far as is known. Bibliography. Newport, "On the organs of Reproduction and Development of the Myriapoda," in Phil. Trans., 1841 ; "On the Nervous and Circulatory Systems," ibid., 1843 ; Koch, System der Myrinpoden, 1847 ; Karsch, " Zur For- menlehre der pentagonen Myriapoden," Arch. f. Naturg., 47 Jahrg., pt. 1 ; Kolrausch, "Gattungen u. Arten derScolopendriden," ibid. ; Grenadier, " Uber die Augen einiger Myriapoden, "Arch.f. Mikr. Anat., vol. xviii.; Voges, "Beitrrigo zur Kenntniss der Juliden,"Z. /. wiss. Zool., vol. xxxi. ; Gulden Steeden-Egeling, "Hydrocyanic Acid of Fontaria," in Arch. f. Physiologic, Pfluger, vol. xxviii. ; Scudder, " Archipolypoda, a subordinal Type of spined Myriapods from the Car boniferous Formation," in Trans. Bost. Soc. Nat. Hist., vol. iii. ; Lubbock, "On Pauropus," Trans. Linn. Soc., vol. xxvi. ; Bode, "Polyxemts lagttrus, ein Beitrag zur Anat. &c.," Zeitschr.f. ges. Naturw., Halle, 1877 ; Ryder, "The Structure and Affinities and Species of Scolopendrella," Proc. Acad. Nat. Soc. Philad., 1881 ; Menge, "Myriapoden der Umgegend v. Dantzig," Neueste Zschr. d. Naturforscli . Gesell. in Danzig, iv., pt. 4; Packard, "Scolopendrella and its Position in Nature," Amer. Naturalist, vol. xv. ; Wood Mason, "Notes on the Structure, post-embryonic Development, and systematic Position of Scolopendrella," Ann. and Mag. Nat. Hist.,lSSS ; Moseley, " On the Structure and Development of I eri- patits capensis" Phil. Trans., 1874; Gaffron, "Beitriige zur Anatomie und His- tologie von Peripatus," Zool. Beitriige von A. Schneider ; Balfour, "The Anatomy and Development ot Peripatus capensls," Quart. Journ. Micros. Sc., 1883, and A Treatise on Comparative Embryology, ch. xvii. (H. N. M.) MYRISTICA. See NUTMEG. MYROBALANS. See LEATHER, vol. xiv. p. 382. MYRON, one of the chief sculptors of the older Attic school, was born at Eleutherse on the borders of Boeotia and Attica, and flourished in the middle of the 5th century B.C. He was, like Phidias, a pupil of Ageladas of Argos. He worked almost exclusively in bronze ; the only known exception is his wooden statue of Hecate at ^Egina. He made some statues of gods and heroes, but these were not the works on which his fame rested. The ancient critics, as quoted by Pliny, censured his inability to represent the feelings of the mind ; hence the lofty ideals of Phidias and the Attic school in general were beyond the scope of his art. His works seemed to live and move before the spec tator; but he could make an athlete hurling the discus, not a Zeus hurling the thunder. His most famous works were the Cow, the runner Ladas, and the Discobolus. Of the first, which Avas esteemed his greatest work, no copy is known, and, though thirty-six epigrams celebrate the realism and the life of this animal, which might be mistaken for a living cow, none of them give any information as to the attitude in which it was represented. The statue of Ladas is also unrepresented in modern museums ; no imitation has yet been found. Ladas, an Argive runner, died from over-exerting himself in the long race at the Olympic games. To judge from two epigrams, Myron represented him in the mohient of his supreme effort, with flanks con tracted as if the last breath had gone out from them and was still hovering on the open lips. The copies that have been preserved of two other works of Myron make it easier to realize the qualities that the ancient critics praise in him. The Discobolus is known from several copies, the best being a life-size statue in the Massimi palace at Rome. The athlete is represented at the moment when, after swinging the discus (five pounds in weight) back to the full stretch of his arm, lie is quickening every sinew to begin the forward motion, and to employ in delivering the discus the full strength of every muscle and the whole weight of the body and the impetus acquired by the longest possible swing of the arm. A similar moment, the critical point when one motion is suddenly transformed into its opposite, was seized in another work, of which several copies remain. Its discovery is due to the penetration or Brunn, and, though his ingenious combination has not yet found universal acceptance, it will probably be confirmed by future dis covery. He compared a relief on the Acropolis of Athens, described by Pausanias without the artist s name with the words of Pliny, (My r<m fecit) Satyrum admirantcm tibias et Mincrvam, and recog nized imitations of this scene on an Attic coin, a vase-painting, and an Attic relief, in which Marsyas is represented starting back with outstretched arms before the goddess Athena. He also recognized the figure of Marsyas alone in a marble statue of the Lateran museum,