494 



Forty- fifth Report on the State Museum. 



admit water currents to the brachia (Terebratulinla, Magellania, 



etc.), or to extend the brachia when they are protrusible, as in 



a. Hemithyris, etc. In Lacazella mediterranean the 



\§ brachial valve in opening may traverse an arc of 



90°, but no other species is known to possess this 

 capacity. The viscera are separated from the 

 fig. 98.— l a c a - cav ity of the brachia by a vertical mem- 



zella mediter- J m < '' 



ranea, with the branous wall, which is an extension of the 

 iif e VeS ci J e xcTzT-P a ^ um or man ^ e - The shell-cavity is, there- 

 duthikrs.) fore, divisible into a posterior or visceral cavity, 



and an anterior or brachial cavity. 



Fig. 99. 

 The valves and a portion of 

 body cavity into a posterior or 

 the other parts is as follows: 



25, pedicle. 56, 



28, capsule of pedicle. 57. 



;-i2. upper mantle lobe. 57' 



88, lower nianile lobe. 59. 



40, 40a, brachia 61, 



46, 46a, brachial canal. 63' 



48, 48a, crural canal. 64, 



48a' aperture <>f same 67, 



68, oesophagus. 68, 



54, stomach, 71, 

 56, inteatine. 



— Rhynchonella (Hemithyris') psittacea. 



the mantle removed, showing the vertical wall (88) dividing the 



visceral, and an anterior or brachial chamber. The notation of 



blind extremity of intestine. 

 b, c. d, liver. 

 , hepatic canals. 

 80 gastroparfetal baud. 

 Uioparletal band. 

 68" mesentery, 

 genital organs, 

 ventral runnel of oviduct, 

 tube of same. 



72, 71', 78* anterior and |»>s 

 terior adductors. 



46 



diductors. 



75, 7?, accessory diductors. 



79, pedicle-muscle. 



98, heart. 



96, aorta 



96, pallial artery, 



96' 96" dorsal an d ventral 

 branches of same, 

 (Bronn after Hancock). 



