2 4 6 



JAM1.S I KNKsT KlMiRKM. 



also. -pcries are to be met with which are characterized by both 

 white and red corpuscles. Thus, for inst., Lalnt/oplax buskii 

 makes an exception by lodging cells with hyaline granules to- 

 gether with such ones which contain red pigmented granules, 

 both kinds being nearly equal in number." 



The origin and functions of the "amoebocytes with colorless 

 spherules" is problematical. According to Cuenot ('Qib) they 

 may arise from leucocytes by the addition of spherules of protein 

 and are hence to be regarded as food carriers. 



42 



41 



43 



FIG. 38. 

 FIG. 39. 

 FIG. 40. 

 FIG. 41. 

 FIG. 42. 

 FIG. 43. 

 FIG. 44. 



Hemocyte, C. japonica. Side view, cam. Inc., X 1300. 

 Hemocyte, C. japonica. Surface view, cam. luc., X 1300. 

 Hemocyte, C. chronjhelmii. Surface view, cam. luc., X 1300. 

 Vibratile corpuscle, Stichopus californicus, cam. luc., X 1300. 

 \ 'ibratile corpuscle, Ophiopholis aculcala, cam. luc., X 1300. 

 Yibratile corpuscle, Strongylocentrotits drobachiensis, cam. luc., X 1300. 

 Yibratile corpuscle, S.franciscanus, cam. luc., X 1300. 



3.' The Hemocytcs. 



Theel ('21) describes a series of "red blood corpuscles" from 

 the perivisceral fluid of the Holothuroidea, excepting the forms 

 with tests, as Psoltis. In his discussion of these cells, he calls 

 attention to the fact that the content of these corpuscles was 

 first noted by Semper ('68) who suggested that this material was 

 of the nature of hemoglobin. Howell ('85) advanced the s.mie 

 suggestion with regard to the same type of cell in certain species 

 of Thy one and Cucumaria. Cells of this type were also observed 

 in the Holothuroidea by Cuenot ('91 1>>. Knoll ('93) and Kollman 

 ('08). These cells were described as spherical or elongate ovoid 

 cells with a definite limiting nn ml UMIIC which was elastic, but did 



