11 OEMCRIITION OF PART^. 



• 



oanai ojirn at each extrvmlly, wilh an nilaiKpnimt ut dilatntion nt<>rr or IcM In its rrntnl 

 fOtikM ; vhrncv it In illialni-tliol, aixl l>(fonie<t luliiilAr aiui fi'Mtxl rrp(alo<lly u\<im itself, 

 laerewinff th<-rrl)y in Ii-rif^h until in vuu- inottmrifi it Is nmny tinier tlip Irn^li <>rthe l-<>djr. 

 DirtVr^nt |>->rll<>ii« «>r this raiinl hnv«- r«T«-lv«-<l ilifTinnt ai>|M!lati<>n<. aA it highly i>r<>|«cr, 

 iojtii till- Irtct that rrrtiiin of il<» jwirtt iHTfomi function* <>f n ni<K!ifi<><i charart«T, alth<>iieh 

 all contril'UlJnii ti> oni* m-neral rcMilt In thlx «livi'>l<>n of j>arl>«, conii«nrntive anatorni'ts 

 Iwvv eiuploywl the snnu' nann-!* that have long Ix-en in tis«' in the anatomy uf the higher 

 anininlr), as the foUoiring eniuner.ition will •<ho\v, U^ wit : tho pharj'nx, cMophagus, crop, 

 ciztanl. stomach or chyliflr ventricle, small intestine*, riecnni and rectum. 



The pharyux Is the anterior ]M>rtion «»r bef^inniiu; of the canal. The cavity of the mouth 

 opeiu into it, niui it is an u|>ertiire more or l«ss enlurvetl : it Is, howexi r. U-tter tlevelojicd 

 in ihoM- invcts which masticate tlieir AnkI, the mani)il)ulate<l class. In<le<-<1 it is r«"pmle<l 

 as having no existence except in this class ; for in the suctorial lns«ci, the next i>art, or 

 esoph/u^U'^, is in direct continuity with the hau'>lell.i or suckini; tul>e, which is connected 

 with it l>y two distinct tuix-s. 



Tho e.sophaiHLs, commonly known as the guUtK is a tul>e connecting the pharynx with 

 the crop, or first enlargement of the intestinal canal. It i>asses directly through the thorax 

 and constrictetl jMirt of the insect, terminating in the aUlomen in the cn>p. It Is variahlo 

 in lenijth : it may form om-half \h>- Kncth of the canal, while in other instances it is Ie«s 

 Uian oiH-sixth of smh h-neth. It has a jH-culiarity which has already Ix-en alludi-<l to : its 

 bifurcation anteriorly in the lepid-'ptera, eacli spinil suckinc tulK- extending its branch to 

 it jtLst twhind the head. 



The esopliagus Ls connectwl in the first place with the crop, an enlargement having a 

 dose analuffy in position and form with the c^.p of a bird. It is alsf> called a tlomach by 

 •ome writers on entomology. It is sometimes ]ilaceil on a line with the esoplmguii, when It 

 appears as a simple enlargement of the tul>e ; in other instances it is placed on one side, 

 and then appears more like a sac connecte«! with the es<^)phagus by a short canal, and 

 •rrvitur as a kind of reservoir ; or, in other words, more analogiMis to the c^>p of birds*. 

 In certain i«e«<tles, as tho Cicindcla. tke organ is pnivide»l with a ehmdulnr apjviratus, which 

 secretes an abundant and active juice to soften and otherwise change the fotnl dei>osHe«l in 

 it. In the hemiptera it is remarkably nio<Iifli>«I in function : it loses Its importance as a 

 dep<i«itory of frMni.and becomes a part of a pumping a]>]>aratus ; whence it has been called 

 • fvcikvig ttonuirh. The ins«'ct in this cas^- has the power < if disleniling the sac, and thereby 



* Tt U (troprr In tliU jiUrc to notloa Uip Ikct, that wlille tbcT« »TC nomprona t»H«IIom In tlir (brm mm) Ici^h of 

 Um tlimmlArv canal of inMdn, lhcr<> arc two ino<ilflc*tl<in> that should be partlratarlT niKikm of. nunrlT : Uw 

 bot-flj ha* no oiM-Dui|t at all aoawcrinx to tbo mouth anil pharvax, aixl bcoco cao take do ttoariiiuBCDl , and la tii* 

 lUTt of the wu|> and tw, the n^tum b dowd, and limcc thcit ccoimiiit doc* Dot r«i)Qlrr lti« cracvatioii of ex 

 ■attcr. 



