508 J. H. ORTON. 



gonads (see Fig. 3), and the invaginated form of the pouch described by 

 Legros * is also well shown in some sections (but is not shown in 

 Fig. 3). Thus the structure of this pouch is of the normal female plan. 



The transverse section shown in Fig. 3 shows also an abnormal feature 

 of much interest. On the right side (the reader's left) in the dorsal region 

 of the atrial cavity is a structure resembling a groove opening on to the 

 outer region of the atrium but enveloped by an extremely thin membrane 

 on its pharyngeal side so as to enclose a narrow cavity. This structure 

 arises at about the level of the second right gonadial pouch, and is con- 

 tinued backwards and gradually enlarges to about the level of the seventh 

 right gonad, the groove gradually opening out to this point (see Fig^. 

 4 and 5). 



An examination of a series of sections of the w^hole of the gonadial 

 region of the animal shows, how^ever, that this apparent groove is really 

 a forward continuation of the liver. At about the level of the seventh right 

 gonad the structure assumes the more definitely tubular form of a liver 

 by the divergence of the thin membrane from the groove-like portion 

 which also becomes straightened out (see Fig. 4). The liver retains 

 practically the same characters throughout its length, having its right 

 wall composed of columnar epithelium tucked inwards along the whole 

 of the middle of its length, as shown in Fig. 4, but having the left wall 

 almost entirely membranous (see Fig. 5). At the junction of the liver 

 with the intestine a columnar epithelium is developed on the whole of its 

 wall. Thus the digestive gland in this specimen is highly abnormal ; its 

 condition is very probably correlated with the abnormal state of the 

 sexual organs. 



A careful examination has been made of the tissues for parasites, but 

 nothing of sufficient importance has so far been detected to confirm the 

 suggestion that the hermaphroditism may be due to the influence of 

 parasites. A fair number of small nucleated spherical bodies are present 

 in the cavity o^ the liver, and bodies are present in some of the 

 abnormal intuckings of the intestinal wall which may be parasites, but 

 the methods of staining employed up to the present have certainly not 

 disclosed such an extensive invasion of foreign bodies in the tissues as 

 perhaps one might expect to find in an animal whose sex is abnormally 

 changed by an infection of parasites. 



The occurrence of hermaphrodite specimens of Amphioxus has been 

 recorded previously on only two occasions so far as I know. In 1876 



* M. Legros, " Sur la Morphologic des Glandes sexuelles de V Amphioxus lanceolatus," 

 Comptts-Rendus du Troisieme Congres hiternationale de Zoologie, Leyden,1895. 



