INVERTEBRATA, CRYPTOGAMIA, MICROSCOPY, ETC. 261 



New Family of the Lernseida.* — In his classical work on the 

 Crustacea, M. Milne - Edwards divided the Lernaeida into three 

 families : Chondracauthida, Lcrnasopoda, and Lernseocera ; M. Hesse 

 finds as a result of his researches on a new form [SUjlofhorus Mppo- 

 cephaliis, from the nasal cavity of Baja rostrata) that it is necessary to 

 form a fourth, the Lerna^opalmida. The male is not known, but the 

 females are fixed to their prey by means of a pair of brachiform 

 thoracic appendages which are very long and completely separate ; 

 their superior extremity is terminated by cartilaginous palmar mem- 

 branes which are so united as to seize and hold fast a small cartila- 

 ginous band which is drawn into a point at the two lateral extremities. 

 The brachiform appendages penetrate for their whole length ; and the 

 *' hippocephalic " head has two large lateral eyes ; the sucking organs 

 are retained within the mouth. The body is pyriform in shape, large, 

 and flat ; it is terminated by a central boss, on either side of which 

 there projects a long cylindrical and recurved tube. The ovigeroua 

 tubes are long and large. 



The animal is 5 cm. long, and this great size M. Hesse 

 associates with the length (2 metres) and weight (100 kilogrammes) 

 of its host ; it is probable that it penetrates the resistant muscles 

 of the nasal cavity by so using the "osselet" or band between its 

 brachiform appendages as to give to it a gyratory movement, and so 

 to bring into use the points at either end. The first specimens which 

 came into the author's hands were mutilated, and at first he only 

 observed that the appendages were so arranged at their terminations 

 that they seemed to be adapted to hold something firmly ; a careful 

 examination revealed a small " osselet " of cartilaginous substance 

 and rectangular in form, placed within the narrow rounded hole 

 which these creatures form in the nasal muscles of their host. More 

 perfect examples revealed the relations of this body which had its 

 ends so disposed as easily to recall to the mind the arrangements of an 

 anchor, and M. Hesse found that the creature attached its arms to 

 this band of cartilage, but that when it was touched it quickly leaves 

 go of it, and contracting itself very rapidly withdraws its body from 

 the cavity it has itself formed. 



The head appears to be even more like that of the liorse than is 

 the anterior cud of Hijtpoaimpus, and tliis resemblance is not a little 

 aided by the two hirge lateral eyes : the presence of these eyes is 

 sufficiently remarkable iuasnuieh as in allied forms the females are 

 ordinarily eyeless, and when such organs are present they always 

 occupy a median position. The ova arc not extruded until they have 

 been provided with three pairs of apjjendiigcs, and it is only after they 

 become free that the rotatory organs take on the characters peculiar 

 to the ]>arasite. 



Vermes. 



Optic Organs of Free-living Polychsetous Worms. t — Professor 

 Gruber finds iis ii result of his compiinitive iuvestigatitms that in all 

 the Chajtopoda which he cxaniinid the eye, liowsoevcr mucli it may 



♦ 'Ann. Sci. Nat.,' viii. (iS70) .\rt. No. 15. 

 t ' Archiv. Mikr. Auut.,' xvii. (18710 p. 213. 



