139 



Fit;. 5- lliivedct :if en Ihui i saimiK' Stillint;'. 

 !. 6. Skallen at' en Hun, nii'il Vahierne t:et lukkede, peet 



fra veni^tre SicU'. 

 J v. Saninie uvenfra. 



Tab. XIX. 

 Limnetis hyaclii/Kriis, iMull.T 



Fiu-. 1 



lU. 

 11. 



Lepiemet at' on llun lig.uende i sin naturlige Situs i 

 lioire Yalvel: venstre Valvel Imrttajjet. h Hjertet; 

 ovs en at de ka;;et'(irrniiie .l\t;niaKf-er. 

 Kn Foler af Iste Par. 



Kn at' lie ]iaa sanmie t'a'stede I,uatepapiller, st:erkt 

 t'lirstorret. 



Kn Foler at 2det Par .\ai-ei. 



;\Iundre,ni(>nen seet nedenfra; (.)verl;eben borttaget. 

 M Kindbakkerne; ?».' Iste Par KJæver; m^ 2dct Par 

 Kjiever; oes Spiserøret. 

 Kn Kjievt' af Iste Par. 



l""n af de jiaa Sjiidsen at saninie fieste<le Pigge, sta^rkt 

 forstorret. 



Kn Kja-ve af '2det Par. 

 Haledelen seet fra venstre Side. 

 Samme nedenfra. 



Den bagre Del af Legemet seet ovenfra, fl de om- 

 formede dorsale Lappe af Kxopoditcrne paa Ilde og 

 lOdeFodi.ar; 1 de l>hi.ll'..niiige dorsalePlader; n Hale- 

 tligene. 



Hjertet sei't ovenfra. 



Det forreste Afsnit af Tjc\gemet af en Hun, seet fra 

 venstre Siile (Aarerne mleladte). de sammensatte 

 Oine; oe det enkle Oie; p dettes forreste Ligament; 

 oZ Sandsegruber; æ Fastheftningsorgan ^'?) ; a^ Iste Par 

 Folere; L (")verla:'l)en; M Kindl>akkerne; m' Iste Par 

 Kja'ver; m^ 2det Par Kjiever; »»s Insertionsarea for 

 Skallens Lukkemuskel; J Tarmen; fø lA'veren. 

 Kn Sandsegrulie seet ovenfra. 



Hjernegangliet med de fra samme udgaaende Xerver, 

 tilligemed de sammensatte Oine [0) og det enkle (_)ie 

 oe), seet nedenfra; 02)t Synsnerven; o' Nerver for 

 Iste Par Folere; a" Nerver for Aarerue. 

 Samme Del (u<len de sammensatte Oine\ seet fra 

 venstre Side. I!ogstaverne som paa foregaai'ude 

 Figur. 



Det enkle Oie seet forfra. 

 Skalkja/ileleu med Muskelareaen. 



Tab. XX. 



Liwnctis hrachyurus, i]\lull.) 



Fig. 1. Va\ Fod af 3die 1'ar hos Hunnen. 1 — 5 Endopoditen 

 med sine Knditer; mx Coxallappen; ex Exopoditens 

 ventrale Lap; ex^ deus dorsale Laj); ep f^pij)oditen. 

 » 1 a. En af de til na'Stsidste Endit fa'stede Torne, sta>rkt 

 forstorret. 

 1 b. Coxallappen isoleret, og seet fra den indre Sidiv 



> 2. En Fod af 8de Par. 



3. Kn Fod af 9de Par. 



3 a. Enden af Exopoilitens dorsale Lap, sta-rkt forstorret. 



4. En Fod af Ilte Par. 



» 6. En Fod af 12te (sidste) Par. 



» 6. Legemet af en Han liggende i sin naturlige Situs i 

 venstre Yalvel ihøire Valvel borttaget). 



> 7. Kn Fod af Iste Par hos Hannen. 



12. 

 13, 



14. 



15. 

 l(i. 



Fig. 5. Head of a male, in the same ]iosition. 

 - I). Slu'll of a female, with the valves closely shut, seen 



from the left. 

 3 7. Same, from above. 



Plate XIX. 



Limnetis hrachyurus, i:\riill.) 



Fig. 1. r>o<ly of a female, hdug in its natm'al position in 

 the right shell; left valve re»moved. h, heart; ovs, 

 i>ne of the cakedike egg-masses. 

 » 2. An antenna of the 1st pair. 



2 a. ( Ine of the olfactory papilUc on the same, highly 

 magnified. 

 - 3. An antenna of tlie 2nil |iair foarsl. 



4- ( (ral regiiin, seen from bidow: lalirum I'emoved. M, 

 mandibles; Hi', 1st pair of maxillæ; m', 2nd jiair of 

 maxilhe; oes, i esophagus. 



6. A maxilla of the 1st pair. 



5 b. < hie of the spines at the end of the same, luLihly 



magnitied. 

 (J. A maxilhi of tbi' 2nd pair. 



7. C'auilal part, seen from the left. 



8. The same, from lielow. 



0. Posterior part of tlie Ijody, seen fi'om above. //, the 

 transfornu'd dorsal lolies of the exopodites in the 

 9th and 10th j.airs nf legs; I, the leaf like dorsal 

 lamellæ; ti. camlal lobes. 



10. Heart, seen from above. 



11. .Vnterior ]iart of the body of a female, seen from the 

 left. ,(_)ars nmitteil . (J. c(lml^ound eyes; OC, ocellus; 

 p, its front ligament; ol, sensory pits; x, affixing 

 organ (?); a', 1st pair of antennæ; L, labrum; M, 

 mandil)les; t»', 1st pair of maxilhe; m', 2nd pair of 

 maxilhe; ms. area of insertion of the adductor umscle 

 .if thi' shell; I, intestine; Ir, liver. 

 A sensory iiit, seen from aliove. 



Cerebral ganglion with the nerves issuing from it, 

 and the compound eyes 0) and ocellus {oc), seen 

 from below, oj^t, optic nerve; a', nerves for the 1st 

 pair of antenna:'; a", nerves for the oars. 

 Same part (without the compound eyes), seen from 

 tlu' left. Lettering as in lig. 13. 



12. 

 13. 



14 



16. Ocellus, seen from the front. 

 Ki. Shell liland with muscular area. 



Plate XX. 



Limnetis hrachyurus, (jMull.) 



Fig. 1. A leg of the 3rd )iair in the female. 1 — 5, endopo- 

 dite. with its endites; mx, coxal lolie; ex. ventral 

 lolie of exopoditt'; ea;', its dorsal lobe; ep, epijiodite. 



1 a. One of the sidnes on the penultimate endite, highly 

 magnitied. 



lb. Coxal lobe isolated, and seen from^the inside. 



2. A leg of thi' 8th pair. 



3. A leg of the '.ifh j.air. 



3 a. Knd of dorsal lobe of exopodite, highly magnitied. 



4. A leg of the 11th pair, 



5. A leg of the 12tb ilast^ pair. 



6. Body of a male lying in its natural position in the 

 left valve (right valve removed). 



' 7. A leg of the 1st pair in the male. 



