524 



SCIENCE. 



[Vol. I., No. 18. 



Action of the heart during hibernation. — C. 

 Ashton lias studied the action of the heart in hiber- 

 nating helices. The observation is difficult owing to 

 the opacity of the parts and the necessity of guard- 

 ing against the temperature radiating from the ob- 

 server's body. The pulse seems to be irregular, or 

 rather, perhaps, to pass through active and quiescent 

 cycles. Absolute inactivity of the heart probably 

 does not occur during hibernation. Under scrutiny, 

 the pulsations vai-ied from three to twenty-two per 

 minute. The animal is extremely susceptible to 

 changes of temperature, as a touch of the finger 

 will often double the rate of pulsation, which also 

 rises with exercise or motion. — {Quart, jouni. conch., 

 1882.) w. H. D. [1046 



Malacological notes. — Dr. W. Kobelt proposes 

 to issue through Theodor Fischer, in Kassel, an ico- 

 nography of European shell-bearing marine raoUusks, 

 which is much needed, and will be extremely useful 

 to malacologists. It is to contain anatomical as well 

 as conchological details, aud will be issued iu parts 

 containing four plates each, in a colored and an un- 



colored edition, at the rate of a volume annually. 



Dredgings by Admiral Spratt in the Black Sea have 

 been examined by Dr. Jeffreys, who finds them to 

 contain six species of shells, hitherto unrecorded, from 

 that basin, one of which (Trophon breviatus) appears 

 to be peculiar. He regards the Black Sea zoologi- 

 cally to be a mere offshoot of the Mediterranean, as 



the latter is of the North Atlantic. Bergh has 



printed in the mittheilungen of the zoological station 

 at Naples a contribution toward a monograph of the 

 nudibranchiate genus Marionia of Vayssifere, — a 

 group belonging to the Tritoniidae, and of which a 

 few species are known in the Mediterranean and Red 

 Seas. The paper is illustrated by a beautiful colored 

 plate. — w. H. D. [1047 



VERTEBRATES. 



The heart as a suction-pump. — It has long been 

 discussed whether the ventricle of the teart is not 

 only a force-pump in systole, but also a suction-pump 

 in diastole, actively dilating, and drawing blood into it 

 from the veins. That within the closed thorax there 

 is, due to the negative pressure prevailing in that cav- 

 ity, an active diastole cannot be doubted ; but is there 

 such a diastole when the chest is opened, or does then 

 the blood returned to the heart from the veins merely 

 push apart the flaccid walls of the heart-cb ambers ? 



Goltz and Gaule have, among others, maintained 

 the doctrine of such active diastole. Even with an 

 open thorax, they found a negative pressure occurred 

 in the heart during some part of acardlac period • and, 

 though their method of work did not enable them to 

 determine at what moment in the heart's cycle this 

 negative pressure occurred, they assumed that it was 

 during the diastole. Moens, however, in a subse- 

 quent noteworthy paper, brought forward experi- 

 mental and other proofs that the negative pressure 

 in the left ventricle occurred at the end of the systole, 

 and not in the diastole at all : if so, the heart was 

 not a suction-pump. Jager now returns to the ques- 

 tion ; and taking as starting-points the assumptions, 

 that, if negative ventricular pressure occurred at the 

 close of the systole it must show itself in the aorta, 

 but if diu'ing diastole in the auricles, he concludes 

 that it is diastolic ; since his experiments show that 

 at no time is there a negative pressure in the aorta, 

 while there may be such in either auricle. Accord- 

 ingly, he maintains that the heart is a suction-pump. 

 We may remark, however, that the correctness of his 

 primary assumption is by no means certain : hence 

 his whole argument falls to pieces. There is, on the 



contrary, strong reason to believe that the ventricular 

 contraction lasts after closure of the semilunar 

 valves, and that it is just at this very end of the sys- 

 tole that the negative intracardiac pressure occurs. — 

 (Pfliig. archw,xxx. 491.) H. N. M. [1048 



'Mastzellen' of connective tissue. — The 

 granular cells described in 1877 by Ehrlich, and since 

 known by the name of ' mastzellen,' have been 

 studied by Raudnitz. Their frequency in different 

 organs and animals is very variable. They are gen- 

 erally abundant in the tongue, but are rare or wanting 

 in the human tongue, and could not be found in any 

 part of the rabbit. They are wanting in embryos, 

 and are few in young animals. Raudnitz supposes 

 that they are cells undergoing mucous degeneration. — 

 [Arch. mikr. aiiat, xxii. 228.) c. s. M. [1049 



Haematoblasts of Hayem. — These little granu- 

 lar masses, which were first accurately described by 

 Max Schultze (1865), have since been frequently ob- 

 served ; but their meaning and history have not been 

 hitherto satisfactorily determined. Hayem believed 

 them to be red blood-globules in process of develop- 

 ment, and accordingly named them haematoblasts. 

 Bizzozero has studied these bodies, which are about 

 one-half the diameter of the red globules, in the cir- 

 culation of living mammalia as well as in extravasated 

 blood. In the latter they change with extreme rapid- 

 ity, and each one becomes a centre from which the 

 filaments of fibrine radiate, upon coagulation. When 

 unaltered, these little disks are colorless, and bounded 

 by nearly parallel surfaces. They have no nucleus, 

 and contain two optically distinct substances, and 

 exhibit with various reagents essentially the usual 

 changes of protoplasmic bodies. Bizzozero denies 

 that they change into red blood-corpuscles, as main- 

 tained by Hayem. The bulk of the memoir deals with 

 the relation of these bodies to thrombosis and coagu- 

 lation. The closing section is devoted to an account 

 of these plates in cold-blooded animals. [Are not 

 these bodies products of degeneration, perhaps amy- 

 loid?] — {Virchow's arch., Nov., 1882. Resume in 

 Arch. ital. bioL, n. in.) c. s. m. [1050 



The origin of apnoea. — In his third contribu- 

 tion. Knoll discusses the origin of apnoea. When 

 rabbits in which the vagi are intact are made apnoeic 

 by free artificial respiration, spontaneous respirations 

 again appear only after the blood has become suffi- 

 ciently venous to stimulate the vaso-eonstrictor, car- 

 dio-inhibitorv, and other centres in the medulla. This 

 depression of the irritability of the breathing-centre 

 is so great, that, even when the blood-flow to the brain 

 is cut off, no breathing-movements are called forth, 

 although the vaso-constrictor centie becomes power- 

 fully stimulated. This is in opposition to the results 

 obtained by Rosenthal. The difference between his 

 and Rosenthal's results may be owing, he thinks, to 

 the latter having experimented upon animals with 

 the chest opened. Although the respiratory centre 

 in the apnoeic animal does not respond to stimuli 

 from the blood, yet reflex stimulation, electrical or 

 mechanical stimulation of the vagus or of the nasal 

 mucous membrane, for instance, can still produce 

 inspiratory contractions ; not so readily, however, as 

 in an animal not apnoeic. The production of apnoea 

 in artificial respiration he attributes, in part at least, 

 to a rhythmic stimulation of the vagi. In rabbits in 

 which both vagi were cut, he succeeded in bringing 

 about apnoea by artificial respiration only in five 

 cases out of twenty ; and in three of these there was 

 evidence of diminished irritability of the respiratory 

 centre from other causes. In the other cases a flat- 

 tening of the respiratory curve could be perceived, — 



