S E R 



extending from the nine upper ribs to the bafis of the fca- 

 pula. It is irregularly four-fided, broader below and in 

 front than above and behind. It arifes from the eight or 

 nine upper ribs by as many diftinft pointed portions, which 

 are firlt tendinous, then flefhy. The firlt, which is broad, 

 very thick, (hort, aytd dHHnft from the reit, arifes from the 

 outer edge of the firlt rib, towards its back part, from the 

 fecond, and from an intermediate aponeurolis. The fecond, 

 third, and fourth, broad and thin, arife from the external 

 furfaces of the fecond, third, and fourth ribs, in oblique 

 lines direfted from above and behind, downwards and for- 

 wards. The four or five lalt, narrower and increafing in 

 length downwards, arife from the upper edge and external 

 furface of the eorrefponding ribs, and are placed between 

 the digitations of the obliqtius externus abdominis. From 

 the origins juft enumerated, the fibres of the mufcle proceed, 

 divided, particularly below, into fafcicuU eorrefponding to 

 each digitation, fcparated by cellular lines, and foon form- 

 ing three diftinft portions. Tiie fuperior divifion is thick, 

 narrow, and fhort, extends from the two firlt ribs to the fu- 

 perior angle of the fcapula, afcending a little, and covering 

 the upper edge of the fecond portion, to which it is united. 

 The middle "divifion, broad and thin, goes from the fecond, 

 third, and fourth ribs to the upper three-fourths of the bafis 

 of the fcapula ; its fibres proceed horizontally from before 

 backwards, except the inferior ones, which defcend a little. 

 The inferior portion of the mufcle pafl'es from the fifth, fixth, 

 feventh, and eighth ribs to the inferior fourth of the bafis of 

 the fcapula, and the inferior angle of the bone. This part 

 is thick, radiated, broad in front, and narrow behind. The 

 fuperior fibres of this portion go nearly horizontally from 

 before backwards ; the inferior ones are direfted at the 

 fame time from below upwards, and are more obhque in 

 proportion as they are lower : they are united towards the 

 inferior angle of the bone. 



The external furface of the ferratus is covered, towards 

 its lower and anterior part, by the fkin, at the lower and 

 pofterior part by the latidimus dorfi. Above and towards 

 the front it is covered by the peftoral mufcles, by the axil- 

 lary vellels, and the brachial plexus. In the reft of its ex- 

 tent it is in contaft with the fub-fcapularis. The external 

 furface covers the feven or eight fuperior ribs, the external 

 intercoftal mufcles, and behind a portion of the ferratus 

 fuperior poiticus. The upper edge of the mufcle is the 

 fhortelt, extending from the margin of the firlt rib to the 

 fuperior angle of the fcapula : the inferior, much longer, 

 reaches from the eighth or ninth rib, or about two inches 

 from its cartilage, obliquely to the inferior angle of the fca- 

 pula. The anterior edge is the longeft, and fixed to the ex- 

 ternal furface of the eight or nine firft ribs, by the diliinft 

 pointed ferrx or digitated portions, from which the name of 

 the mufcle has been derived : the pofterior is fixed to the 

 front edge of the bafis of the fcapula, and of the fuperior 

 and inferior angles of the bone. 



The aftion of the ferratus anticus produces two different 

 effefts, according as the fcapula or the ribs are the fixed 

 point. In the firft cafe, the fcapula being fixed by the tra- 

 pezius, rhomboid and levator mufcles, it draws the ribs out- 

 wards, elevating thofe to which it is fixed by its lower digi- 

 tations : in this refpedl it is a powerful agent of infpiration, 

 concurring with the peftoral mufcles. In the fecond cafe, 

 it carries the fcapula forwards, antagonizing the rhomboid, 

 trapezius, &c. But it moreover draws the inferior angle 

 forwards, and confequently moves the upper and anterior 

 angle of the bone, forming the . (houlder, upwards. Thus 

 the ferratus anticus is an important mufcle in fupporting 



S E R 



burdens carried on the {houlders. In this cafe the diaphragm 

 and abdominal mufcles are put in aAion to draw down the 

 ribs, fix them, and prevent them from yielding to the effort* 

 of the ferratus. 



Serratls Major Anticus. See Serratus yintkus. 



Skrratcs Pofllcus Inferior, (dentele potterieur inferieur ; 

 lombocoftieii,) is a broad, thin, and Hat mufcle, fituated at 

 the lower part of the back, and extending from the fpinous 

 proceffes of the vertebra to the ribs. It arifes from the 

 fpinous proceffes of the two laft dorfal vertebrae, of the 

 three firlt lumbar, and the intervening interfpinal ligaments, 

 by a broad aponeurofis, compofing one half of the mufcle, 

 common to it and the latiffimus dorfi, compofed of parallel 

 fibres, directed obliquely upwards and outwards. This 

 aponeurofis is connected in front to that of the tranfverfus 

 abdominis, and by its lower edge to the obhqu'is interaus. 

 The mufcular fibres, pafTing with the fame obliquity as thofe 

 of the aponeurofis, form four fafciculi or pointed ferrated 

 portions, of which the firft and broadeft is fixed to the lower 

 edge, and near the angle of the fecond falfe nb ; and the three 

 others, which are fucccflivcly fmaller, are alio attached, by 

 aponeurotic fibres, to the lower edge of the three fucceeding 

 ribs, farther from the angle. The pofterior furtaceof this 

 mufcle is covered by the latiflimus dorfi. The anterior fur- 

 face covers the three laft falfc ribs, the external intercoftal 

 mufcles, the longiflimus dorfi and facrolumbahs, and the 

 tranfverfus abdominis. The upper edge is continuous with 

 the thin aponeurofis, wiiich immediately covers the longifli- 

 mus dorfi and facrolumbnlis. 



By drawing downwards the lower ribs, this mufcle afGfts 

 in expiration. It car.not produce any tffeft on the fpine : 

 it will confine the muicles lying at the fide of the ipiiie, and 

 thus has the fame effedt as the ferratus poilicus fuperior and 

 the fafcia extended between them. 



Serratu.s Pojlicus Superior, dentele pofterieur fuperieur ; 

 dorlocoftien,) is a very imall and thin mufcle, flat and four- 

 fided, placed at the upper part of the back. It arifes from the 

 ligamentura nuchas, the laft cervical Ipinous procefs, and 

 the two or three upper dorfal ones, by a thin aponeurofis, 

 compofed of parallel fibres, direfted obliquely downwards 

 and outwards. The flefhy fibres follow the fame direftion, 

 forming a thin ftratum, which terminates in four fmall fafci- 

 culi or ferrated portions, ending in aponeurotic fibres, 

 which areinferted in the upper edges of the ft-cond, third, 

 fourth, and fifth ribs, near their angles. Il is covered ex- 

 ternally by the rhomboideus : and it covers the fplenius, 

 tranfverfalis colli, the vertebral mufcles, the ribs, and the 

 eorrefponding intercoftal mufcles. 



It will have the effedt of elevating the ribs, and thereby 

 of enlarging the cheft, or aflifling in infpiration. 



SERRAVALLE, in Geography, a town of France, in 

 the department of Marengo, O'; the Scrinia ; 12 miles S. of 

 Tortona. — Alfo, a town of France, in the department of 

 the Sefia ; i8 miles N. of Vercelii. — Alfo, a town of Italy, 

 in the duchy of Mantua ; 24 miles S.E. of Mantua. — Alfo, 

 a town of Italy, in the Trevifan, i\ miles in circumference, 

 partly on a plain between two mountains, and partly on the 

 mountains near the river Mafcliio, which runs through the 

 middle of the town, and has its fource in a fm;dl h.ke in the 

 higher part of the town. At the extremity of the market- 

 place is the public palace, and at the lower end the cathedral 

 church, containing fome good paintings. The town and its 

 fuburbs comprehend two parilhes, and 30 churclies, that of 

 St. Augufta attra£t;ng notice by its noble architecture, and 

 its long noble ftaircafcs. Here are alio two nionafterics, and 

 two nunneries. The inhabitants are induftnous, and trade 



particularly 



