INVERTEBRATA, CRYPTOGAMJA, MICllOSCOPYj ETC. 885 



There is very great variation in the dimensions of the jaws ; the 

 greater number do not average more than y^o inch in length, but a few 

 are ^ inch long and yL iuch wide. In order to form an idea of the 

 relative length of worms with similar jaws, the principal jaw-plate was 

 measured in a specimen of the existing Eunicea sanguinea (whose body- 

 was 8 inches long), and was found to be i inch long aud j^^ inch wide. 

 If the length of these animals is in proportion to that of their jaws, 

 then the largest of the fossil jaw.> would belong to an annelid of about 

 13 inches in length, whilst the greater jiart would not be more than 

 3i inches. 



Organization of Batrachobdella Latasti, C. Vig.* — This Hiru- 

 dineaij was found living parasitically upon a Batrachian of Algeria, 

 Diploglossus pidus, which, added to a certain external resemblance, 

 led to its being taken for Glossiplionia algira. Like the latter, it has 

 only two eyes, but is otherwise distinguished by its smaller size, 

 its more regular form, not attenuated in front, its green colour, and 

 its proportionally larger posterior sucker. The following are the 

 results of its anatomical study by C. Viguier. 



Genital Organs. — The genital orifices are in the male on the twenty- 

 first ring, and in the female between the twenty-third and twenty- 

 fourth. There is no developed penis, but a simple button, as in the 

 Glossiphonke, which is generally placed a little to the right of the 

 median line (looked at from the lower surface). The epididymi are 

 very large, and, after a certain number of folds, each gradually 

 narrows into a very slender deferent canal. Twelve testes relatively 

 large are arranged in two regular and parallel rows. The female 

 apparatus is composed of two very small pyriform ovaries, from which 

 start slender oviducts, passing into a very small transverse and always 

 exactly median matrix situated immediately above the vulva. 



Digestive Apparatus. — There is, as in the Glossiphonice, an exsertile 

 trunk, behind which the cesoj)hagus has the aspect of a muscular tube 

 with longitudinal and annular fibres. Above the genital orifices 

 there is a large, pyriform, brownish swelling, visible by transparent 

 light in the living animals, and which is constituted, from without 

 inwards, by somewhat voluminous brown cells, and by large clear 

 cells with a brilliant nucleus, disposed all round the lumen of the 

 digestive tube. Immediately behind this swelling, which performs, 

 no doubt, the function of a liver, are the first lateral cfeca, which pass 

 in front of the first testes ; five other cfeca on each side pass between 

 the testes of each row. Lastly, a seventh pair of narrow caeca comes 

 behind the last pair of testes. The axial portion of the digestive tube 

 presents between the cfeca small turbid cells, perhaps hej)atic cells. 

 Behind the seven pairs of narrow caeca, and where the cavity of the 

 body is no longer occupied by the testes, are four pairs of large caeca 

 — the first two directed slightly forward, the third nearly transverse, 

 the fourth directed backward. The terminal portion of the digestive 

 tube makes a small loop to the left, and is then directed in a straight 

 line to the anus. 



* 'Comptes Eendus,' Ixxxix. (1870) p. 110; 'Ann. and Mag. Nat. Hist.,' iv. 

 (1879) p. 250. 



