62 CEYLON PEARL OYSTER REPORT. 



canals which unravel themselves into two dorsal and two ventral canals which run 

 down the neck (Plate IV., tigs. 55 and 56), and a series of muscle-fibres which pass 

 to the base of the bothridia. These muscle-fibres gather themselves up into stout 

 strands which run down the neck, and these, together with the nerve-cords and 

 the lateral pairs of water vascular canals, make up all there is in the neck. 

 The neck and the proglottides are alike striated, the cuticle being very clearly- 

 ridged. The striatum of the neck is more apparent than that of the body, possibly 

 because the proglottides to some extent break it up. The longitudinal muscles can 

 be seen running down the neck. The proglottides begin at the base of the neck, 

 and their appearance can be judged by Plate IV., fig. 51. In the ripe proglottides 

 the central uterus and the lateral yolk-glands take the form of a coil with three 

 limbs. The coil starts from a point in the posterior middle line, passes forward and 

 turns either to the right or left and returns again posteriorly, then passes across the 

 proglottis and runs forward again. One curious feature is that the turning to the 

 right or left goes in pairs. A pair of proglottides with the turning to the left 

 is followed by a pair with the turning to the right, and so on. These markings, 

 which somewhat resemble the Greek key pattern, give a characteristic appearance 

 to the proglottides. The transverse bar which seems to connect the uterus with 

 either the right or left row of vitellaria is formed of the genital duct and penis. The 

 genital pores are lateral and alternate in pairs, first a pair on the left side, then a pair 

 on the right. The penis is covered with minute spines. 



The diagnosis of EcJwneibotJirium javanicum is as follows : 



Length from 9 millims. to 12 millims. Head with no myzorhynchus ; the four 

 bothria divided by two longitudinal ridges into three rows of areolas, one of these 

 being terminal ; then come three longitudinal rows of seven areolas, and at the base 

 is a transverse row of seven large areolas. A long narrow neck occupies one-third 

 to one-half the body-length. Cuticle very definitely striated. 



Habitat : Rhinoptera javanica, in the intestine. 



Echinobothrium rhinoptera, n. sp. Plate IV., figs. 57, 58 and 59. 

 Along with the Eniochobothrium gracile a few specimens of a curious Cestode 

 which we place with the genus Echinobothrium were found. The specimens measured 

 about 3 millims. in length, the head slightly over 0"2 millim. As a rule in the genus 

 Echinobothrium the head is succeeded by a portion called the " Kopfstiel" by 

 German writers. This bears eight rows of very characteristically shaped spines. In 

 our specimen, however, the head is borne by a long " neck," devoid of spines. This 

 "neck" is - 3 millim. in length, and in the fresh condition it seemed strobilized, but 

 in the stained and mounted preparations this seems not to be so much a real 

 strobilization as a .more or less regular wrinkling of the cuticle. Unfortunately, the 

 number of specimens was so small that we could not settle this point by an appeal 

 to the knife. 



