696 DR. p. E. BEDDARD ON 



obvious, and in being sii:igly distributed remind us of Coiug7iiq, 

 and not of the AcoleidjE where the layers are stronger. I have 

 re-examined other species of Linstoioia to ascertain whether this 

 peculiarity is or is not confined to Linstoivia lemuris. I find the 

 same delicate transverse fibres between the longitudinal bundles 

 in L. a7)ieivce and also in Oochoristica mari^iosce, a species which, 

 as I have already pointed out in describing it *, is hard to 

 i-efer decisively to either Linstoioia or Oochoristica, a matter 

 to which I recur later. However, in a Linstowia from Echidna, 

 the specific identity of which I am not certain, there was no 

 supplementary transverse layer of muscles. Nor did I find 

 anything of the kind in Oochoristica from Tamandtia teira- 

 dactyla, the structure of the body-wall of which would, howe\ er, 

 I'ender this arrangement impossible, as may be seen from my 

 figure of the same t. 



Tiae longitudinal muscles are disposed in an inner and an 

 outer series. As to the former, there is a layer of thick fibres, 

 sometimes two or three or even five or six massed togetlier. 

 Outside this there lies another layer of the same kind, but 

 imperfectly defined. The outer layer of longitudinal muscles 

 consists merely of scattered fibres of less size than those already 

 dealt with. There is here no sharply defined formation of 

 layers. The additional transverse fibres already mentioned are 

 associated with the inner layer of stouter muscle-fibres. 



The excretory system is, like that of some other species referred 

 to the two genera Oochoristica and Linstowia, characterised by a 

 network quite easy to detect but not easy to map accurately. 

 I have found at least three branches arising from the ventral 

 vessel and extending towards the middle of the proglottid. 

 These do not, however, cross as unbroken tubes, but are dis- 

 solved into a network. 



The testes lie dorsal to the ovary and vitelline gland and 

 lateral of the same. They extend from side to side of the 

 proglottid, but do not invade the cortex. I counted about 

 nineteen in a single row. There are two of these rows in a 

 transverse section, and hoi'izontal ones show also two rows, in 

 parts increased to three. The cirrus-sac in this species is small 

 and extends a little way beyond the nerve-cord- — in fact, as far as 

 the lateral vessel. This might appear to mean that it is after all 

 not so small ; but the width of the proglottids is such that the 

 sac occupies but a short space of the transverse diameter, and it 

 is thus relatively small. The sac lies at the bottom of a deep 

 genital cloaca ; this involution from the exterior narrows abruptly 

 internally to a narrow passage which opens into a wider sac, 

 which receives the male and female ducts and is a common male 

 and female atrium. Such an arrangement is common among 



* P. Z. S. 1914, p. 289. 



t Ihid. p. 270, text-tie:. 4, D. It will be noticed that there is no marked gap 

 between the longitudinal layers allowing of the intercalation of a transverse layer as 

 in Linstowia lemiiris. 



