CONTENTS. XV 



PAGE 



Prep. 37. Dissection of Common Earthworm (Lumbricus 



terrestris), showing its nervous system . . . 121-123 



Prep. 38. Dissection of anterior segments of same animal, 



showing its reproductive organs 124-126 



Prep. 39. Specimen of Medicinal Leech (JKriw^o mec^icma^is) 127-129 



Prep. 40. Dissection of Medicinalljeech (^Ilirudo medicinalw), 



showing nervous and digestive systems in situ . 129-131 



Prep. 4 1 . Dissection of Medicinal Leech (Hirudo medicinalis), 



showing nervous system 131-133 



Prep. 42. Dissection of same animal, showing the reproduc- 

 tive and segmental organs in situ 133-136 



Prom the Class Platyelminthes. 

 Prep. 43. Specimen of Many-headed Bladder-worm (Caenurus 



ctmicidi) 136-140 



From the Class Asteroidea. 

 Prep. 44. Specimen of Common Crossfish {^Asterias ruhens) . 141-143 

 Prep. 45. Dissection of Common Crossfish (Asterias ruhens), 



showing digestive and motor systems . . . 143-145 



From the Class Holothurioidea. 



Prep. 46. Specimen of Angular Sea-Cucumber (Cucumaria 



jientactes) 145-147 



Prep. 47. Dissection of Angular Sea-Cucumber (Cucumaria 

 2)entactes), showing motor, digestive, respira- 

 tory, and reproductive systems 148-158 



(Relations of Echinodermata to Coelenterata 

 and to Vermes severally at pp. 152-157 of the 

 Description of this Prepaiation.) 



From the Class Anthozoa. 

 Prep. 48. Dissection of Sea- Anemone {Actinia crassicornis), 

 showing its various external and internal 

 organs 158—160 



From the Class Hydrozoa. 

 Prep. 49. ^-pecimen of Sesi-Th' (Serttdaria ahietina) . . . 160-163 



From the Class Spongiadae. 

 Prep. 50. Specimen of Fresh-water Sponge {Sponyilla lacu- 



stris) 163-166 



