6l6 ORDER HETEROTRICHA. 



" Ueber einige neue pelagische Infusorien," contributed to the ' Jenaische Zeitschrift ' 

 for the year 1873. 



Codonella galea, Hkl. Pl. XXXI. Figs. 32 and 33. 



Lorica helmet-shaped, slightly longer than broad, rounded and inflated 

 posteriorly, expanding at the frontal margin, constricted behind this region, 

 its substance verrucose, transparent anteriorly, apparently tesselated through 

 subdivision into regular polygonal areas, each of which encloses a minute, 

 siliceous (?) particle ; animalcule twice the length of the lorica when ex- 

 tended, dilated anteriorly to a width equal to or surpassing the aperture of 

 that structure, entirely filling the lorica when retracted ; tentacular cilia 

 equalling the lorica in length ; inner membranous border or collar bearing 

 the lappet-like appendages, shallow, not exceeding in depth the length of 

 the lappets ; colour golden yellow ; endoplast band-like, curved, longitudi- 

 nally disposed; contractile vesicle posteriorly located. Length of lorica 

 1-250". Hab. — Saltwater: Messina and Lanzarote (Haeckel). 



The lorica of this species corresponds so remarkably in shape and structure 

 with that of Tintinnus lagcmda, that, compared in their uninhabited condition, it 

 is scarcely possible to separate the two. The animalcule of this last-named type, 

 as figured by Claparede and Lachmann, appears, however, to exhibit no essential 

 deviation from the ordinary members of the genus to which it is allocated, though at 

 the same time there would seem to be an indication of an inner circular peristomal 

 border corresponding with the membranous collar of the present species, but showing 

 no trace of the lappet-like appendages. 



Codonella orthoceras, Hkl. Pl. XXXI. Fig. 38. 



Lorica elongate, conical, about two and a half times as long as broad, 

 tapering backwards from the wide oral aperture towards the sharply 

 pointed posterior extremity, but interrupted in the posterior half by a 

 globose inflation ; the posterior half rough and coarsely nodular, the anterior 

 smooth and finely annulate transversely ; animalcule when contracted 

 retreating to the inflated posterior region of the lorica. Length of lorica 

 1-125". Hab. — Salt water : Messina. 



Haeckel considers the Tintinnus cindus of Claparede and Lachmann, Pl. XXXI. 

 Fig. 10, of which the lorica only has been observed, as probably closely allied to, if 

 not identical with this form. Its contour and structure, on comparing the two, is 

 found, however, to be too distinct for the admission of their absolute identity. In 

 T. ductus the lorica, with the exception of the abruptly dilated oral aperture and 

 distinct tooth-like posterior termination, is cylindrical throughout, smooth, and 

 delicately annulate transversely from one end to the other. It is at the same time 

 possible that this form, in common with many others referred to in the genus 

 Tintinnus by the authorities quoted, on the strength only of the contour and struc- 

 ture of the lorica, will, when the enclosed animalcule is known, have to be referred 

 to the present or some other equally distinct pelagic genus. 



Codonella campanella, Hkl. Pl. XXXI. Figs. 34-37. 



Lorica bell- or helmet-shaped, about one and a half times as long as 

 broad, the posterior extremity produced into a long, subulate, conical point, 

 the anterior border widely dilated, transversely annulate throughout, but 



