C 2.0
Preserved invertebrates
Earthworms, crayfish, grasshoppers, squid, starfish and clams, and the phylum survey sets that carry a whole comparative sequence in one order.
Invertebrates are mostly supplied plain, because in most of them there is nothing worth injecting: an open circulatory system has no vessel tree to fill. The variable that matters here is not grade but condition — whether the appendages are intact, whether the specimen has been relaxed before fixing so it is not curled into a ball, and whether it is the size the exercise assumes.
A curled crayfish is a genuine teaching problem. A specimen fixed in a contracted posture has to be forced open on the tray, which tears the very structures the lesson is about. Ours are relaxed before fixing, which is slower and is the reason an invertebrate specimen costs what it costs.
The survey sets exist because comparative anatomy is the whole point of this group. Eight phyla, one representative each, labelled, in one box, is a sequence rather than a pile — and it is priced as a set rather than as the sum of eight singles.
Name these on the order
- Species and binomial
- Named on the order, because “starfish” covers several genera with visibly different arm counts and surface texture.
- Size band
- Stated in inches. The difference between a 3″ and a 5″ crayfish is the difference between a struggle and a demonstration.
- Preparation
- Relaxed before fixing, appendages intact, and injected only where the animal has a closed system worth filling.
- Holding fluid
- Formalin-fixed or formalin-free, as for vertebrates.
- Pack size
- Each, pack of ten, pack of twenty-five, or as a labelled survey set.
All of them appear on your written quotation before a purchase order is raised. See ordering.
C 2.1 Prices
Published prices
Catalogue figures for this group, reviewed September 2026. The whole catalogue is priced on one page if you would rather compare groups — see prices.
| Specimen | Size | Each | Pack of 10 | Pack of 25 |
|---|---|---|---|---|
| EarthwormLumbricus terrestris | 6–8″ | $2.15 | $19.40 | $44.00 |
| CrayfishProcambarus clarkii | 3–5″ | $4.80 | $44.00 | $102.00 |
| GrasshopperRomalea microptera | 2–3″ | $3.10 | $28.50 | $66.00 |
| SquidLoligo sp. | 5–8″ | $5.60 | $52.00 | $120.00 |
| StarfishAsterias sp. | 4–6″ | $4.25 | $39.00 | $90.00 |
| ClamFreshwater, whole | 2–3″ | $3.90 | $35.50 | $82.00 |
| Sea star, largeDisplay grade | 7–9″ | $18.40 | — | — |
| Phylum survey setEight phyla, one each, labelled | Set | $62.00 | — | — |
Catalogue prices are USD per unit at the pack size stated, exclude shipping, handling, hazardous-materials surcharges and any applicable tax, and are catalogue ranges for planning a requisition rather than an offer or a quotation. Reviewed September 2026. A figure for your order is confirmed on a written quotation. See the disclaimer.
Questions Preserved invertebrates
Questions about this group
Specific to preserved invertebrates. The general questions — ordering, purchase orders, substitutions, returns — are on the FAQ page.
Why is a relaxed specimen worth paying for?
Because an unrelaxed one is fixed in whatever posture it died in, which for a crayfish or a grasshopper means curled and clenched. Opening it on the tray then tears the joints, gills and mouthparts the exercise is about. Relaxing before fixing takes longer and is the difference between a specimen that demonstrates and one that has to be fought.
What is in the phylum survey set?
Eight preserved representatives, one from each of eight phyla, each labelled with its common name and binomial, in a compartmented box: sponge, cnidarian, flatworm, roundworm, annelid, mollusc, arthropod and echinoderm. It is built for a comparative sequence run over several sessions rather than for a single dissection.
Do invertebrates come injected?
Some do. A crayfish can be injected to show the open circulatory spaces and a few of the larger molluscs are supplied injected. Most are not, because an open circulatory system has no closed vessel tree to fill and injecting it would show nothing a plain specimen does not. Where an injected preparation exists we say so on the line.
Are these suitable for middle school?
Earthworms, starfish, clams and grasshoppers are the usual middle-school set: small, cheap enough to buy spares, and with clear structures that survive an inexperienced first cut. Squid is also popular and is more forgiving than it looks. Crayfish reward a steadier hand.
Catalogue The other groups
The rest of the catalogue
Frogs, fetal pigs, cats, rats, mink, perch, sharks and the rest of the dissection sequence, at the injection grade the lesson actually needs.
Algae, protozoa, bacteria, fungi, plants and live invertebrates, shipped on a calendar set by the organism rather than by the warehouse.
Sterilised barn owl pellets in first and second quality, which are different products for different lessons and are priced separately.
Scalpels, scissors, probes, forceps, pins and trays, and the assembled student and instructor sets built from them.
Telephone with the lesson, not the catalogue number
Tell us what the lesson has to show, how many students are working in pairs and which week it is scheduled for. We will name the species, grade, size, fluid and pack that fit and put it on a written quotation.
Niles Biological, Inc. · 9298 Elder Creek Rd, Sacramento, CA 95829