1865.] Mr. Bastian Anatomy and Physiology of Nematoids, 871 



when the heart has ceased to supply blood to the pulmonic capillaries, during 

 the period previous to coagulation, the blood may be driven or drawn over 

 the pulmonic circuit, may be oxidized in its course, may reach the left side 

 of the heart, may be distributed over the arteries, and that, thus distributed, 

 it possesses the power of restoring general muscular irritability and the 

 external manifestations of life. Hence I infer that resuscitation, under the 

 limitations named, is a possible process, and that it demands only the ele- 

 ments of time, experiment, and patience for its development into a de- 

 monstrable fact of modern science. 



Various modifications of the experiments to which I have had the 

 honour to draw the attention of the Society are in hand ; and if I am 

 allowed the privilege, they will form the subject of another communication. 



XIV. " On the Anatomy and Physiology of the Nematoids, parasitic 

 and free; with observations on their Zoological Position and 

 Affinities to the Echinoderms." By HENRY CHARLTON BASTIAN, 

 M.A., M.B. (Lond.), F.L.S. Communicated by Dr. SHARPEY. 

 Received June 13, 1865. 



(Abstract.) 



After commenting upon the many conflicting statements which have 

 been made concerning the anatomy of these animals, and more especially 

 with regard to the presence or absence of a nervous system, and of real 

 organs of circulation, the author alludes to the increased interest which 

 has lately been thrown over this order by the discovery of so many new 

 species of the non-parasitic forms, marine, land, and freshwater. 



He has entered fully into the description of the tegumeutary organs, 

 and has recognized a distinct cellulo-granular layer intervening between 

 the great longitudinal muscles and the external chitinous portion of the 

 integument. This layer is one of great importance in the economy of 

 these animals ; the author looks upon it as the deep formative portion of 

 the integument from which the chitinous lamellae are successively ex- 

 creted. It is bounded internally by a fibrous membrane, which serves as 

 an aponeurosis for the attachment of the four great longitudinal muscles ; 

 and the well-known lateral and median lines which have so long been a 

 puzzle to anatomists are, he says, in reality nothing more than inter-mus- 

 cular developments of this layer. In some species each of the lateral lines 

 contains an axial vessel, though in very many others nothing of this kind 

 is to be met with. A periodical ecdysis of the chitinous portion of the 

 integument takes place in all Nematoids during the period of their growth. 



The author agrees with Dr. Schneider as to the nature of the transverse 

 fibres attached to the median lines. They are contractile prolongations 

 from the longitudinal muscles, and may be considered extrinsic muscles 

 for the propulsion of the intestinal contents, since the intestine itself has 

 no muscular tissue in its walls. 



