BIOL 3360L Vertebrate Comparative Anatomy Laboratory -- 2015
Lab 3 “Primitive Vertebrates… Agnathans”
 Prelab preparation:
*Review Lab 1 material for Quiz 1
 Quiz 1 (Protochordates)
 Review/discuss Lab 2 (Fossil Field Trip)
*Fossil “show and tell”
 Introduction and Orientation to Agnathans
*Lecture notes
*Eddie and the Hagfish
*Lamperea “Vampira de Agua”
 Lamprey (Petromyzon sp.) anatomy:
*External anatomy… Review the section on pg. 20 in the handout provided. Review spatial terms as
appropriate. Locate the following structures and determine the function of those with asterisks:
o Head
o Eye*
o Trunk
o Pineal gland*
o Tail
o Nostril*
o Caudal fin
o Buccal funnel*
o Dorsal fins
o Papillae
o Urogenital papilla
o Teeth*
o External gill slits*
o Lingual teeth*
*Sagittal and Cross sectional anatomy… Review pgs. 21-25 in the handout provided. In
reference to each system, locate the following structures and know the function of those with
asterisks:
o Pineal gland*
o Heart*
o Nostril*
o Liver*
o Nasal canal*
o Intestine*
o Olfactory sac*
o Gill lamellae*
o Brain*
o Branchial pouch
o Spinal cord*
o External gill opening*
o Notochord*
o Branchial tube*
o Myomere*
o Kidney*
o Myosepta
o Dorsal aorta*
o Tongue*
o Cranial cartilages*
o Pharynx*
o Gonads (ovaries or testes)*
o Velar tentacle
*Ammocoete anatomy… Review pgs. 25-27 in the handout provided. Using the low power objective of
a compound microscope observe the prepared slide of an ammocoete larva (keep in mind similarities
that would have placed these in the Cephalochordata group). Locate the following structures and
know the function of those with asterisks:
o Oral hood
o Liver (and gallbladder)*
o Oral tentacles*
o Intestine*
o Pharynx*
o Notochord*
o Dorsal fin
o Spinal cord*
o Caudal fin
o Anus*
o Eyespot*
o Gill slits*
o Brain*
o Gill filament*
o Esophagus*
o Velum*
Answer the following questions
Describe the ecology/natural history of hagfish (Where do they live? What do they eat etc. ?).
Are hagfish monoecious or diecious?
Describe the ecology/natural history of lamprey (Where do they live? What do they eat? Etc.).
Are lamprey monoecious or diecious?
What is an ammocoete larva and how does its feeding strategy compare to that of cephalochordates?
What are the 3 major steps hypothesized to be involved with early evolution of vertebrates?
T or F? Lamprey breathe (take in oxygen) via water coming in through their median nostril.
Explain the truth or fallacy of lamprey having ears.