14 ^rt. 3.— T. Kaburaki : 



tractor of the pharynx, pass obhque longitudiDally from the root 

 of the latter organ, through the parenchyma to the dermal 

 musculature. TJie numerous fibres are peculiarly distributed in 

 Ect. limuli around the atrial chamber apparently without order, 

 running irregularly and outwardly in the parenchyma (PL 1. fig. 

 8.) 



In structural respects the muscle fibres show nothing peculiar, 

 and consist, as usual, of the inner granular and the outer fibrillous 

 layer. The latter is more strongly stainable than the former. 



Parenchyma. 



The parenchyma constitutes the greater portion of the body- 

 substance, occupying all the interstices between the various 

 organs. It generally consists of two sorts of cells, one of which, 

 subject to considerable variation in form, is usually multipolar. 

 In each there exists an ovoid or rounded nucleus. Processes of 

 these cells come into connexion with one another, giving the 

 appearance of the sponge reticulated fibrous connective tissue. 

 The other is rounded or ovoid cells, the plasma of which is very 

 finely granular and nearly homogeneous. They are usually 

 designated under the name of "stamm" or "formative" cells, 

 and are easily distinguished by a somewhat largei* nucleus contain- 

 ing chromatin in noticeable abundance. They lie chiefly in the 

 lateral parts of the body and take part in the regeneration or the 

 formation of the tissue, as mentioned by several authors. 



In St. trigonocephala the pigments, which are of somewhat 

 coarse granules and of a dirty greenish colour, occur abundantty 

 in the anterior region, as already stated. In the deeper tissue, 

 below the dermal musculature, the granules are intercellular in 

 position, never intracellular, and considerably well developed in 

 the region of eyes. No sign of pigments was detected in the 

 epidermis, unlike Heterochaerus austraUs, and also no special 

 pigment cells are anywhei-e present. 



