358 
MISS E. J. BECK ON THE MUSCULAR 
exactly similar to the anterior pericardio-ventral muscle (136), except that it runs on 
the posterior instead of the anterior side of the dorso-ventral muscle (71). 
The pericardium is not continued into the five subsequent segments of the metasoma, 
and accordingly we do not find there any muscles representing the veno-pericardiacs of 
the mesosoma and first metasomatic segment. 
I. 
Il. 
Reference to letters in Plates LXXVII., LX XVIII., LXXIX. 
Is, Is, Is, 1s,. Lung-sacs (blood-containing envelopes of 
Chelicera, first appendage. 
Chela, second appendage. 
l1.-v1. Four ambulatory appendages. 
yu.—xu. Six segments of mesosoma. 
xuL—xvi. Six segments of metasoma. 
(Ay 
B. 
. Anterior third coxal entosclerite. 
. Posterior third coxal entosclerite. 
. Anterior fourth coxal entosclerite. 
QHAHGQ?Hs# Bea 
First coxal entosclerite. 
Second coxal entosclerite. 
. Posterior fourth coxal entosclerite. 
Fifth coxal entosclerite. 
. Preoral entosclerite. 
. Postoral entosclerite. 
. Carino-sternal entosclerite. 
. Canal in plastron through which nerye-cord 
passes. 
. Ventral portion of carapace turned under 
anteriorly (transparent). 
. Vascular space in pericardio-ventral muscle. 
. Alimentary canal. 
. Arthrodial membrane, covering the body 
between the chitinous plates. 
ap. Anterior process of plastron. 
arc. Arterial canal-aperture in posterior flap of 
plastron through which the dorsal vessel 
runs. 
cam. Camerostome or upper lip. 
car. Carapace. 
ce. Central eyes. 
cg. Coxal glands. 
dr. Dorsal ridge of plastron. 
dv. Dorsal vessel (anterior continuation of 
heart). 
ge. Gastric canal-aperture in posterior flap of 
plastron, through which the alimentary 
canal runs. 
go. Genital operculum (seventh appendage). 
le. Lateral eyes, 
imp. 
m. 
m, 
the lung-books) in four last segments of 
mesosoma. 
Lateral median process of plastron. 
Mouth. 
Aperture in flap of plastron through which 
muscle 83 passes. 
. Aperture in flap of plastron through which 
muscle 65 passes. 
Divisions between muscles. 
Thoracic metasternite. 
Muscular fibres. 
. Nerve-cord. 
. Nerve-ganglion. 
. Pericardium. 
. Postanal spine. 
. Pecten (eighth appendage). 
Posterior flap of plastron. 
. Pharynx. 
. Plastron. 
Posterior process of plastron. 
Subneural process of plastron. 
Suprapectinal chondrite. 
s. Sternal sclerite on which pectines are carried 
in second segment of mesosoma. 
zw. Cut edge of carapace. 
y. Cut edge of tergites. 
1, Antero-posterior muscle (prosoma). 
2, Arthrodio-tergal obliquus muscle (prosoma). 
3-8. Antero-posterior muscles (mesosoma). 
9-14. Arthrodio-tergal obliquus muscles (meso- 
soma). 
15-20. Latero-dorsal muscles (mesosoma), 
21-24. Median antero-posterior muscles (meso- 
soma). 
25-30. Lateral antero-posterior muscles (mesosoma). 
31-34. Arthrodio-sternal obliquus muscles (meso- 
soma). 
35-38. Post-stigmatic muscles (mesosoma), 
