448 Dr. E. A. Andrews on a new Species o/Phoronis. 



at each end of the crescentic base, of a large carpel-like or 

 spoon-shaped organ, opening by a wide longitudinal slit into 

 the extra-branchial or anal space, but facing towards the 

 mouth (from which these organs are separated by the row of 

 branchiae between mouth and anus). The cavities of these 

 organs are ciliated and lined by a peculiar glandular epithe- 

 lium. At the base of each is situated a spherical "sense- 

 lobe," apparently corresponding to the "glandular pit" of 

 P. Kowahvshii as described by Benham, and having its 

 ciliated cavity opening in common with the basal part of the 

 slit in the above carpel organ. The function of this large 

 carpel-shaped organ is unknown, but may be supposed to 

 have some connexion with the tube-building habit, possibly 

 as an organ for collecting or fixing sand-grains to the 

 secreted chitin-like tube. 



The body-wall presents in close contact with the inner 

 aspect of its well-developed "supporting-tissue" layer trans- 

 verse fibres (apparently muscular) , internal to which is a very 

 well-marked system of longitudinal muscles. Anteriorly 

 these muscles form conspicuous ridges, a section of one of 

 which shows the fibres to be arranged in a markedly pinnate 

 group (each fibre is cylindrical, with abruptly pointed ends). 



The branchias are ciliated on the lateral sides as well as on 

 the oral side, and in the latter aspect have numerous uni- 

 cellular glands, which continue down in the walls of what 

 may be distinguished as the pharyngeal part of the digestive 

 tube. The oesophagus and first stomach are characterized by 

 the possession of a definite longitudinal ridge of ciliated 

 gland-cells, which in the stomach forms a groove similar to, 

 if not homologous with, the ciliated groove in the sipunculus. 

 The position of this ridge is such as to lie close to the large 

 blood-vessel (afferent vessel of Caldwell) and facing the pos- 

 terior division of the body-cavity. 



In the first stomach a peculiar process of intracellular 

 digestion takes place, irregular ridges of epithelium rising 

 up around one or more large diatoms, and enclosing them in 

 vacuoles within a syncytium-like multinucleated protoplasmic 

 mass. 



The epithelium of the second stomach is histologically 

 different from that of the first. The intestine contains balls 

 or cylinders of broken diatom-shells. 



In one apparently perfect specimen sections show only 

 spermatozoa in various stages of formation, while fragments 

 of other individuals contain eggs in process of formation. As 

 far as can be told from the imperfect material at band this 

 species of Phoronis is not hermaphrodite, or at least the two 



